[Open Assets] Social-Links Pack 1.3

Despite 6+ months of development, I wasn't able to do much for this update, but I did 2 new racers and made a few sprites fixes.

NEWCOMERS:
* Ulala Serizawa
* Akinari Kamiki

FIXES:
- Slightly darkened Nanako's Outlines, just to give her more contrast.
- Fixed and polished some Icons, for visibility purposes.

Thanks for supporting this project, even during my absence!

Finally made this update to implement both Fan-Favorites and unconventional choices.

NEWCOMERS:
* Akihiko Sanada
* Mitsuru Kirijo
* Kazushi Miyamoto
* Mamoru Hayase
* Ryotaro Dojima
* Naoki Konishi
* Shu Nakajima

Thanks for supporting this project, despite its messy development!

Making this update for July, because the racers I made so far are cool enough to be released now.

NEWCOMERS:
* Eikichi Mishina
* Lisa Silverman
* Katsuya Suou
* Fuuka Yamagishi
* Ken Amada
* Shinjiro Agaraki
* Anthro Koromaru

Thanks for supporting this project!