Django-bulbs

- Added homepage video player and updates to bulbs-styles.
- To install:
* Add `bulbs.homepage_player` to installed apps
* Add `styles/bulbs-styles/components/homepage-player.scss` to Pipeline
* Add `styles/bulbs-styles/components/video-carousel.scss` to Pipeline

- Added `video_redirect` view for videohub reference.

- Added `child_label` to entry serializers metadata.

- Added `filter_weighted` flag to `TunicClient.get_campaigns()`

- Added `AbstractInfographic.get_infographic_type_name` method.

- Added styling for mobile ads in bulbs-styles