Load textures from file list

- Renamed defs to end in "Types" ex. Projectiles -> ProjectileTypes

- Created texture loading system
-HOW TO
- Put files in Textures directory
- Add filename to TextureFilenames.txt
- Add texture definition to TextureDefs.h
- When you want to use the texture, bind using the TextureTypes enum

- Better memory management, added cleanup for BMP arrays