RetrOSMC Launcher for OSMC

Update containing fixes and rebranding of the RetrOSMC launcher from this script: https://github.com/mcobit/retrosmc

Credits

• mcobit who developed the RetrOSMC installer script: https://github.com/mcobit/retrosmc
• jcnventura3 for the original launcher add-on
• gabrielmagno who fixed executable shortcut issue that I've included: mcobit#55

http://dev.grantgarrison.com