Option to limit update frequencies

[twjacobsen]

Looking through the source, it seems to me that the service updates every 10 minutes, when media is not playing.
Would it be possible to limit this to only update when entering the home screen or the library? Or maybe disable updating after X minutes of user inactivity. After all, there's no reason for updating when XBMC is not in use.
With the current implementation, my server wont ever go to sleep, because each service refresh triggers a MySQL query, which in turn wakes the server/prolongs the sleep-timeout.

[ghost]

Can you look at the alternative_random branch. This branch updates the random items (those that are updated every 10 minutes) after playback ended and library updated instead.