Rename directory stats -> data.
More MAX_LEVEL use.
Recomment lz deecompression.
Truncate MAX_LEVEL + 1 if it exceeds 8 bits.

If MAX_LEVEL was set to 255, the value could not fit into a byte.
Add a dereferenced stats screen function.

This was probably used in the stats screen in JP versions.
It fell out of use when the stats screen layout was redon in localization.
Use {hl,de,bc}coord macros wherever possible.
Remove the FuncCoord macro.

Variables can't use labels, so a macro that doesn't use variables is better suited.
Clean up the growth_rate macro.
Experience growth rate constants.
Bump pokemontools for better compression.

A goal is to be able to reproduce the original lz data in the repository.
In the meantime, make it smaller than before.
Merge pull request #254 from yenatch/master

Better compression, macro cleanup, use MAX_LEVEL everywhere.

- move stats -> data (like pokered).
- remove FuncCoord and use {hl,bc,de}coord for all tilemap loads.
- use MAX_LEVEL where needed.
- update pokemontools for better compression, and recomment related code.
- growth rate constants