Delete splinext.pokedex.model.

Unused auto-generated cruft.
Clean up imports.
Use identifiers instead of names: move methods.
Use identifiers instead of names: everything else.

I think that's the rest of them. Except for the tests.
Item pages: Link to Bulbapedia and Serebii.
Don't try to show HG/SS overworld sprites for Mega Evolutions.
Fix obdurate.

The font images were renamed *ages* ago.

Fixes #103.
Make caching play nicely with obdurate.

The obdurate cheat code subtly alters the way flavor text is rendered.
Most pages are cached. Caching doesn't take the effect of cheat codes
into account. Cheat codes are therefore very flaky.

This is a long-standing bug.

The fix is simply to add the cheat code state to the cache key. An
alternative would be to bypass the cache when cheat codes are enabled.

Caveat: this commit causes location and type pages, which don't have
any flavor text, to have redundant copies cached.
Make this loop clearer.