[Open Assets] srb2bld - SRB2 Build/Package manager CLI

Features:
1. Added builds:
- SRB2 Edit (SRB2 fork made by Luigi Budd),
- Radio Racers (Dr. Robotnik's Ring Racers fork made by blondedradio),
- Ultimate Lowee Builder (Ultimate Zone Builder for BlanKart made by NepDisk).

Fixes:
- Fixed issue with compiling/linking SRB2 Classic, SRB2 Kart Moe Mansion, SRB2 Kart Galaxy, SRB2 Kart HEP on macOS,
- Fixed copying SRB2 Classic binary for Linux and potentially others builds using "find" command to dynamically copy binaries from source in the future,
- Fixed issue of creating separate binaries in install path for SRB2 custom builds due to using configuration directory name (with branch in suffix) after upgrading build.

Other:
- Replaced URL to Codeberg one for source code of SRB2 Classic,
- Updated README.md,
- Updated compatibility table.

Features:
1. Added builds:
- SRB2 v2.2 Classic,
- SRB2 Project Astral,
- SRB2 Kart for Android
2. Added support for path to single asset file in formats pk3, kart, etc. with SRB2BLDASSETPATH and SRB2BLDEXTRAASSETPATH

Fixes:
- Fixed incorrect main.pk3 hash for BlanKart,
- Fixed not fully uninstalling build, if cmake -D flags were applied by user previously for Ring Racers builds,
- Fixed extracting issue with "data" directory for Ring Racers custom build - caused by set extra asset with SRB2BLDEXTRAASSETPATH,
- Fixed copying icons and other files for custom Ring Racers builds,
- Fixed assets path for created SRB2 Kart/Ring Racers custom build Flatpaks and AppImages,
- Fixed naming of Flatpaks, config directories and binaries for builds,
- Fixed building issues of Ring Racers, Ring Racers Noire, Ring Racers HEP2, Ring Racers HEP3, Ring Racers Freaky Build on macOS

Other:
- Updated README.md,
- Updated compatibility table,
- Added dependency for macOS users to install "xxhash" package, in order to have correct hash after building BlanKart's main.pk3 file,
- Cleaning code and removing unnecessary flags for copying single file.

Features:
1. Added builds:
- SRB2 Top Down,
- XSRB2,
- SRB2 SF94-Serv,
- SRB2 Riders,
- Super SRB2 Kart Z,
- Super Bomberman Blast 2,
- ShufflarB2,
- SRB2 Live,
- SRB2 LoZ,
- BlanKart,
- Ring Racers HEP3,
- Ring Racers for Android,
2. Old builds based on SRB2 v2.0 (and SRB2 Final Demo) are now compiled as 32-bit binaries only (issue #32),
3. Variable SRB2BLDDEVMODE can prevent updating build.

Fixes:
- Fixing issue with permissions for git command in subfolders of SRB2 builds,
- Fixes regarding downloading and extracting assets,
- Fixed building issues for SLADE and Aseprite on Linux,
- Fixed rendering of welcome page when opening SLADE for Linux,
- Fixing linking of pthread for SRB2 Fusion Advance,
- Fixed conflicts with libpng,
- Fixed issues of not copying of some compiled binaries and icons,
- Fixed issues of ignoring globbing on Alpine Linux's shell,
- Fixed issue of not running compiled builds from desktop menu entries, which are installed in user's home path,
- Replaced links for Alpine Linux container packages from git.alpinelinux.org to GitHub mirror due to captcha challenges,
- Fixed issue of not executing flatpak command to build flatpak due to command POSIX incompatibilty with Dash shell,
- Fixed issue of not switching branch/tag on specific build,
- Other fixes that are specific to issues on Linux distributions, Windows and macOS.

Others:
- Updated README.md,
- Updated compatibility table,
- Replaced links for SRB2 Reveries source code and assets,
- Replaced links to NepDisk's builds (issue #33),
- Added option to run instaled Mono command installed on Linux if Mono bundle fails,
- Removed unused commented code,
- Added more comments to parts of code.

- Fixed issue #30 caused by missing asset file 3drend.dll during christmas time for SRB2 Final Demo,
- Fixed issue "Error: choosing an image from manifest list docker://ubuntu: no image found in image index for architecture" by adding "--platform linux/i386" for SRB2 Final Demo and SRB2 JTE,
- Removed dependencies installation check for SRB2 Final Demo and SRB2 JTE which was replaced by copying 32-bit libraries from docker/podman container,
- Fixed errors undeclared variables for SRB2 Reveries,
- Updated README.md.

Features:
- Added SRB2 v2.1 Fusion Advance as build target,

Fixes:
- Removed Android builds from upgrade tasks, which caused compile errors,

Other:
- Updated compatibility table,
- Simplified install instructions for Windows users in README.md.

• Replaced link to GitHub repository of SRB2 Reveries,
• Changed default branch for SRB2 Reveries for Android,
• Fixed assets for SRB2 Reveries,
• Removed APPIMAGE compile flag from Makefile to prevent triggering build's AppImage_build.sh script for SRB2 Kart Saturn and SRB2 Kart Neptune,
• Fixed issues with location of assets for custom SRB2 Kart build.

Features:
- Added Ring Racers Freaky Build,

Fixes:
- Corrected links to assets for the latest version of SRB2 TSoURDt3rd,
- Fixed issues of compiling/linking for the latest version of SRB2 TSoURDt3rd by adding libsdl2 to compile and changing version of libsdl2-mixer,
- Fixed issues of not downloading from Google Drive after Google's changes,
- Corrected path to extracted/copied assets to directory for usage of Cmake on macOS,
- Fixed issue of not saving user's configuration flags for later build's upgrade with "srb2bld -up" for Windows,
- Fixed issues upgrading builds on macOS and Windows.

Other:
- Updated README.md,
- Updated compatibility table,
- Changed default branch from Noire to Noire-Stable for Ring Racers Noire,
- Added function to script to download the latest version of assets, if older assets are not possible to download for build,
- Renaming assets for previous versions of build from "Older" to specific build's version,
- Added removal of previously compiled libraries in case of upgrading them to avoid issues with compiling build,
- Added command to copy binaries by dynamically finding for custom builds.

Here is an update that solves issues I detected and were reported by users on Linux distros:
- Steam Deck's SteamOS,
- Fedora Silverblue, Fedora Kinoite, Universal Blue (Bazzite, Aurora etc.),
- NixOS,
- Chrome OS,
- openSUSE,
- Musl-based Linux OS like Alpine and Void Linux.

Fixes:
- Improved detection of read-only root system for Immutable/Atomic Linux,
- Improved detection of passwordless user account in Linux environment (Chrome OS, Chromius OS, Crostini),
- Fixed issue of permission errors within container for Fedora Silverblue/Fedora Kinoite/Universal Blue (Bazzite, Aurora) etc,
- Fixed issue of not able to uninstall build on NixOS,
- Corrected URL check and issue of not downloading for assets from drive.google.com,
- Corrected URL to Ring Racers build to solve issue of not downloading source code,
- Added checks to minimize displaying errors of executing installing dependencies and other stuff,
- Fixed issues of not compiling/linking SRB2 VR, SRB2 Kart VR and wadcli,
- Added building libpng for musl-based Linux distros for issues related with running SRB2 build, especially on Void Linux,
- Fixed libpng12 conflicts,
- Fixed issue of missing libraries for Slade on musl-based distros,
- Added SRB2LEGACYWADDIR variable to AppImage and Flatpak for SRB2 2.1 Legacy to solve issue of not finding game's assets,
- Fixed issues of not installing slade or not patching paths to "/nix/store" files on NixOS, which resulted with messages to patch binaries by NixOS,
- Fixed flake.nix files for SRB2 JTE, Aseprite, Ring Racers, Ring Racers Noire and Ring Racers HEP2 to solve issue of installation failure on NixOS,
- Fixed issues of broken compiled binaries and SDL2 Mixer X library after patching paths to libraries for Linux distros that use Homebrew,
- Fixed issue of not installing missing libraries for Linux distros with Homebrew installed,
- Fixed issue of not finding "flatpak" command on NixOS,
- Added copying 32-bit libraries from container to host for SRB2 Final Demo and SRB2 JTE, to avoid issues of missing packages of 32-bit libraries, especially on openSUSE (issue #29 on srb2bld's Github repo),
- Another improvement for detecting missing packages on Gentoo.

Other:
- Updated README.md,
- Updated compatibility table,
- Added dependency to File package,
- Added cleaning git submodules in build,
- Added icons to batch scripts for running High Voltage Ring on Windows,
- Added checks to avoid copying files for Linux, that would be unused for Windows,
- Added persistent configuration folders for other SRB2 builds flatpaks, that didn't spread in ~/.var path,
- Removed installation of deps for flatpak since flatpak-builder does this by itself,
- Added flatpak-builder flatpak for OS like Steam Deck's SteamOS that can't install package to the system.

Features:
- Added NeptuneFM and Ring Racers HEP2 as new build targets.

Fixes:
- Fixed issue of missing "reveries.pk3" for SRB2 Reveries on macOS.

Other:
- Removed carriage returns in README.md,
- Updated README.md and compatibility table.

Fixes:
- Fixed issue of missing icons and desktop files for custom Ring Racers build on Linux,
- Added link to correct tsourdt3rd.pk3 file to fix "I_Error(): File is old, is corrupt or has been modified:", when running compiled in TSoURDt3rd,
- Updated link to GPG key for APT repository, because old GPG keys caused issues with building docker/podman image,
- Added condition in case of missing debug binary for SRB2/SRB2Kart/RingRacers custom build,
- Fixed errors about upgrading SRB2/SRB2Kart/Ring Racers custom builds,

Other:
- Updated README.md.