Merge pull request #1397 from edx/valera/add_visual_feedback_start_end_time_video

CHANGELOG.rst

cms/djangoapps/contentstore/features/transcripts.feature

cms/djangoapps/contentstore/features/transcripts.py

cms/djangoapps/contentstore/features/video.feature

cms/djangoapps/contentstore/features/video.py

common/lib/xmodule/xmodule/css/video/display.scss

common/lib/xmodule/xmodule/js/spec/video/general_spec.js

...on/lib/xmodule/xmodule/js/spec/video/video_player_spec.js

common/lib/xmodule/xmodule/js/src/video/01_initialize.js

common/lib/xmodule/xmodule/js/src/video/02_html5_video.js

common/lib/xmodule/xmodule/js/src/video/03_video_player.js

.../xmodule/xmodule/js/src/video/06_video_progress_slider.js