Add VLC dependency.
Add initial video support.
Update instructions to include VLC step.
Add initial support for media controller.
Add progress bar for loading video.
Add showing controls after playing is triggered.
Fix play and pause button switching.

Basically just backup state on our own. VLC have a delay between play or
pause and returning the current state, so button is not updating at all.
Add full screen support.

At moment does not work as expected with media controller.
Add saving video time between configuration changes.
Add slide animations for media controller.
Add basic audio files support.
Merge branch 'vlc-integration'