Previously, the "add channel" box was just calling refresh, which
implicitly adds the channel. This adds a separate endpoint for
add_channel, and as a bonus the web ui will navigate you to the
channel after it has been loaded.
- Channels and videos are now objects instead of just dictionaries.
- Copied Etiquette's use of cachemanager mixin to cache those objects.
- Copied Etiquette's use of sql_ methods.
- Copied Etiquette's use of namespaced javascript.
- Copied Etiquette's use of config file.
- Redid video_card css to use grid, better on mobile.
- Improved usage of URL parameters with class=merge_class.
- Wrote some actual content on readme.
