MythTV 0.27 implementing recordedseek table for ms offset during Edl calculations

With help from janbar, the code has been cleaned up and logic has been reorganized. He also split the commits into cmyth/mythtv-cmyth. This replaces PR 135 for my original request. I'm sorry for the new PR.

Original commits and code from: https://github.com/nerddtvg/xbmc-pvr-addons/pull/1