[mythtv] Sleep Timer

[macksold at 7bit.net]

I would find it useful to have some sort of sleep timer that would 
cause MythTV to go to the main menu.  Maybe sleep timer isn't the best 
term since this is not about turning the tv off, it is about keeping 
the server from encoding video all night.

Rather than making this a ui feature I was considering a signal handler 
in MythTV  that would be called via cron.

Comments?