Retroleap v2.0.0-alpha7

Another WIP release for testing.

Changes:
-Surgeon boot screen for LF1000 devices
-Changes to enable didj-fi bringup (not finished yet)
-LF1000 kernel changes for better SD card support
-LF2000 basic touchscreen support
-Fixes to config infrastructure and button mapping

Known issues:
-LF3000 only confirmed to work on Leappad3 (Does NOT work on platinum at this time)
-LF3000 soft power-off not working (have to hold the power button)
-Roms partition not mounting on SD-based devices (e.g. LF3K)