library_bridge: added get_pokehack_sptr function

* Pokehack attempts to make the SaveParser class a singleton
* SaveParser has a private constructor but a public = operator
* This function exploits that and copies the "single instance"
conversions: smarter logic in figuring out Gen 4 game save type

* Save/Trainer only stores D/P, Plat, or HG/SS
* Pokemon stores original game, so look for Pokemon that matches trainer's ID
* If none exists, use less accurate save type
Trainer conversions now use new shared pointers for saves
conversions: PKMDS uses Pokemon in party to determine save's game and trainer's gender