Move MediaPlayerType to ICoreTrack

[Arlodotexe]

Background

The MediaPlayerType on ICore indicates the type of playback supported by a core.

Problem

This should be per-track, not per-core.

Solution

Move MediaPlayerType to ICoreTrack

[Arlodotexe]

Linking #207

[Arlodotexe]

This has been removed from the 0.1.0 milestone to allow us to polish and ship the update faster