[pvr] support for past epg data in timeline view
[epg] fix: incorrect return value in GetSelectedItem()
[pvr] fix: remove wrong condition in ActionPlayEpg()
[pvr] improve implementation of OnClickList() method

* use switch case instead of if else
* use IsActive() to determine if playing the selected item
[pvr] remove unnecessary method PlayEpgItem() and use ActionPlayEpg()
instead
Merge pull request #3696 from xhaggi/epg-past-data

Support for past data in epg timeline view