libretro-cores:
  - adding: 4do, desmume, fceumm, mame, mupen64plus, scummvm,
            snes9x, stella, picodrive, ppsspp and vba

retroarch:
  - added retroarch wrapper for configured cores
  - changed attributes, old retroarch is now retroarchBare*
Merge pull request #3800 from edwtjo/libretro-cores

retroarchWrapper: added wrapRetroArch, libretro-cores: adding some cores