Tried to simplify the sprite loader logic.

Moved detection of `looking frame offset` into an `inner match statement`.
When standing Quote will use look UP + look BEHIND.
Otherwise Quote will use look UP + look DOWN.
(For invalid states I've tried to make Quote use no offset.)

Did this from memory so it likely needs to be tested & patched.
Combine similar matches
Moved `vertical facing` frames into constants.

Also finished simplifying load_sprites.
There are now 3 basic phases:
1. Standing (static sprites)
2. Jumping|Falling (static sprites)
3. Walking (dynamic sprites)

These individually match vertical facing & deal with it in their
own unique ways.

AFAICT this is correct:

Quote can only look down while standing, jumping or falling.
Quote can look up while standing or walking.
Quote cannot look up while jumping / falling.

All other behaviors (horiz. facing) seem unaffected. :thumbsup: