[FIXUP] Rename AnnotatedSeekBar to MarkedSeekBar.
[FIXUP] Better playback controls management.
[FIXUP] Add comments, formatting.
[FIXUP] Optimise AnnotationRenderService.
[FIXUP] Make annotation rendering logic better.
[FIXUP] Comments, formatting.
[FIXUP] Use fuzzy rendering when seeking.
[FIXUP] Tweak seek bar updating frequency.
[FIXUP] Save created annotations.
[FIXUP] Decouple VideoPlayerFragment from activity
[SQUASH] Start work on saving fragment state.