ADD/CLEANUP: PMS v0.9.8.x Timeline API & Status Reporting

Also cleaned up commented out PlexBMC code blocks that was adding bulk
and become confusing when troubleshooting.
As it turns out - the BufferEmpty() & BufferFull() routines dont work
correctly when using Transcoded video as it pauses the player and causes
the PMS transcoding process to stall because gstreamer stops receiving
any data. Suspect its a gstreamer bug but cannot confirm just yet. For
now commeted out the seek pause command when buffer is empty!