firmware: Support camera LED on production boards
firmware: Add gencmds get_mem and get_camera for querying features needed for camera demo
firmware: Suport negative dest_rect coordinates in dispmanx
userland: Updated camera apps, add flips and better diagnostics
userland: Remove warnings in hello_pi demo apps
firmware: fix cartoon camera effect.
userland: Remove unimplemented effects. Tidy up demo mode.
firmware: fiq vchciq breakage on cutdown build
firmware: Fix tainted flag reported on vcgencmd version