More key bindings and events - keyDblClick, keyDown, keyUp, "ctrl+alt+del"

[mmm4m5m]

Description:
Two well knows features. Just added here for reference. (Sorry if description looks bad)

First: About "umount -a" before real power off
Right now, we have shell "reboot" but shell "poweroff" does not work (it does reboot). Real power off using remote control does not "umount -a". In case of "write" operations to usb/jffs2 it could be problem.
We need "notification and delay" before real poweroff - that is how shell script can "umount -a" before power off.
Or, second option, we need to remap "poweroff" to shell script and shell script to be able to call "real power off" function.

Second: Example about "KeyDblClick"
KeyDblClick for Power key, could do "real power off" (default) when single click does "soft power off".
Only if action is assigned to keyDblClick, then single click have to wait 0.5-1 seconds and act after that.