* upstream/stable: (479 commits)
  v5.4.4
  @gkatsev switched to use custom vtt.js from npm. closes #2905
  v5.4.3
  @gkatsev updated options customizer and github-release options. closes #2903
  v5.4.2
  @gkatsev updated grunt-release config. closes #2900
  v5.4.1
  @gkatsev added chg- and github- release for next releases. closes #2899
  v5.4.0
  @gkatsev added ability to release next tag from master. closes #2894
  @gkatsev added nullcheck for cues in updateForTrack. Fixes #2870. closes #2896
  @chemoish emulated HTMLTrackElement to enable track load events. closes #2804
  @gkatsev added a Player#reset method. Fixes #2852. closes #2880
  @nick11703 changed multiline comments in sass with single-line comments. closes #2827
  @gkatsev added Player#tech. Fixes #2617. closes #2883
  @misteroneill updated videojs-ie8 to 1.1.1. closes #2869
  v5.3.0
  @imbcmdth added sourceOrder option for source-first ordering in selectSource. closes #2847
  @forbesjo updated formatTime to not go negative. closes #2821
  v5.2.4
  ...