Add AutoExpire Actions dialog to mythfrontend System Status

[justifiably@…]

I find the list of programs in Systems Status to be expired very useful to watch out for things I hoped to watch being about to expire.

This small patch (against 9620) adds a handy dialog so that expire items can be deleted immediately or auto expire can be disabled. For LiveTV items, disabling auto expire moves them into the Default recording group.

To avoid the nuisance of listing the programs being deleted asynchronously (cf "currently being deleted" in Watch Recordings), I adjusted the auto expire query in the backend to exclude programs with deletepending set. It doesn't look like this will harm anything else. (On the other hand, if there is a huge list of programs to expire, it would be better to manipulate the vector directly rather than repeat the query and re-make the lists, but this can be saved for a later improvement if it seems necessary).

[justifiably@…]

(oops --- the previous version had a space leak, corrected here)

[cpinkham]

(In [9695]) Don't include recordings marked as 'deletepending' in the AutoExpire? list since they are already being deleteed.

References #1629.

[cpinkham]

(In [9697]) Add a popup menu for the items in the AutoExpire? List in mythfrontend's status page. You have the option of going ahead and deleting a recording right away or disabling AutoExpire? for a recording. If you disable AutoExpire? for a LiveTV recording, it will be moved to the 'Default' Recording Group.

Closes #1629 by applying rest of patch by justifiably at cwazy dot co dot uk.