* moved filter constants back to d2enum
* moving key and mouse button enums into d2enum
* moving render type enum into d2enum
* moving input even priority enums into d2enum
* moving terminal enums into d2enum
* Fixes#496 using ebiten.SubImage to Render Section of a Surface.
I had to add matching functions to both animation and sprite to get it to be called
for a sprite object.
* Fixed linter warning on comments for Sprite and Animation.
* Removing what's remaining of the old Sprite re-generation and caching.
* Add PushBrightness to surface
* Highlight selectable objects
Check if mapentity is selectable. (seems reasonable)
Request objects to highlight themselves is required (idk)
