Added new commands

Added New commands 
 Shut down now (Google doesn't seem to ever put "shutdown")
 Reboot now 
reboot into recovery now
 wolfram <query>


These commands all seem to work on my devices.

HOWEVER there is something I don't like about the root only commands (all but the wolfram one). I don't know a way to do the SHUTDOWN broadcast since this isn't a system app. So the SHUT DOWN command works but its a hard shutdown, doesn't give the apps time to gracefully shutdown. I don't know of a way to do this via su.