. going to make new MySprite

!! new MySprite
Loads sprites when on-screen. Unloads them when off-screen.

Contains a sprite.
Saves all properties designed to be forwarded to it.
When created, applies all the properties.

* Given x,y
* Relies on clip for w,h

! Store and load all sf.Sprite properties
Test with manual loading and unloading
texture
texture_rectangle
color
local_bounds
global_bounds

! add MySprite.clip
use it's bounds as w and h
! test with camera-bounded loading/unloading

! add all MySprite subclasses
clip
children
box
animation
clip_animation