Backlight daemon for Zipit Z2

2010-04-26 Tal Stokes
2012-02-20 Joe Honold <mozzwald@mozzwald.com>
2012-03-08 mcmajeres  	  -- added seperate timer for keyboard -- works in conjunction with ebindkeys
2012-03-23 mcmajeres      -- changed blanking control to the framebuffer and added posix timers -- still have a polling loop :(

Manages screen and keyboard backlights:
  -turns them off when lid is closed and on when lid is opened
  -dims them when on battery and brightens them when on AC (or reverse)
  -respects changes made to brightness while running

Thanks to Russell K. Davis for lid switch and AC
plug detection routines, and help