New Raspberry Pi firmware & XBMC Frodo RC3

[Koenkk]

Updated the instructions again (d72c7dd2a14f540a2e387276bfb9543f5114774e). Contains a lot of XBMC fixes for the raspberry pi! Just a few of them:
- https://github.com/xbmc/xbmc/commit/0cfa24e20985d376c4fe4fe41c9e54b4599c6013
- https://github.com/xbmc/xbmc/commit/99a536c4670690758da512e2434a88abc3259ed8
- https://github.com/xbmc/xbmc/commit/4bc6e74f409fe74f8d25524041b59eefd34bee9a
- https://github.com/xbmc/xbmc/commit/cdc73c3840dc693d0fed965720df4d3070527d6d