Sprite rotation capabilities

[exelotl]

The functions TLN_SetSpriteRotation and TLN_ResetSpriteRotation are currently commented out, I guess they are old and unfinished? This would be a very useful feature to have!

[megamarc]

Hi!
Yes, they're an old, unfinished attempt to implement sprite rotation, but I was not satisfied with the sloppy result so I abandoned it. Implementing sprite rotation in software with scanlines and keeping good performance is quite tricky! However it's something that I definitely want to attempt again, I have some new ideas to approach it. It's a personal challenge and it would be a nice feature, of course!