Add an option to select game region

Some roms in genesis collection supports multi-region (US/JP/EU). Example : Bare Knuckle II - Shitou e no Requiem ~ Streets of Rage II (Japan, Europe)

When you launch this game in japan megadrive, the game have text in japan and run in 60 Hz When you launch this game in european megadrive, the game have text in english and run in 50 Hz

Genesis emulators will launch the game with a default region that sometimes can be set.

It could be interesting in recalbox emulation station to add in gamelist an option to specify the region you want to use for the game. The region could be sent to emulatorlaucnher.pyc like other option and emulatorlauncher could send the emulator with correct option.

In a second time, if several region are specified in gamelist for this game, a popup could appear when you launch the game to select the region ou want to use to launch the game.

For example for Bare Knuckle II - Shitou e no Requiem ~ Streets of Rage II (Japan, Europe) A popup could appear and propose choice between Japan and european version.