Started Pokemon-sim rename to LibPKMN

* PKMNsim library changed to PKMN
* CMake scripts changed accordingly
Changed include directory from pkmnsim to pkmn
Changed pkmnsim namespace to pkmn
Continued Pokemon-sim -> LibPKMN conversion
C#: fixed libpkmn-cs.dll build
Changing share/pkmnsim to share/libpkmn and changing environment variables
Removed images submodule
Deleted images submodule...again?
Re-added LibPKMN images module
cmake: changed PKG_DATA_DIR
Merge branch 'LibPKMN'