lib: Pokehack library source added

* Minor alterations for include files to be in same directory
* No functions exposed, all to be used internally
* To eventually be used to parse Generation 3 (R/S/E/FR/LG) saves
Work on game save

* Added Pokehack implementation (untested)
* Added unimplemented get functions in spec_pkmn
* Added game_save classes as friends to spec_pkmn classes as appropriate
Fixed MSVC incompatibility problem with Pokehack integration
Merge branch 'pokehack_integration'