add follow button for sidebar (ref #41)
activity feed update

- add highlight feed top left tag (ref #9)
- add alternate caption for existing highlight feed item (red #34)
Temporarily fixes seeking issue (until transcript is reinstituted)
Merge branch 'develop' of https://github.com/koemei/koemei-widget into develop
Lightbox now allows multiple instances
Different instances of Lightbox now play at proper times
Merge branch 'develop' of https://github.com/koemei/koemei-widget into bugfix/videojs
question form input field resizes on text input