Watched notifications added with configurable cutoff percent.
Styling fixes.
Add information back to settings page for required restart on web interface changes.
Use user_id on user link in activity pane.
Added channels option to Pushbullet.
Possible fix for text encoding issues in Plexwatch importer.
Thread the notifications.
Move most of the notification logic to the notification handler.
First code for independent notifications (not linked to PlexWatch).
New notifications panel in Settings (many types still untested).
Standardise the parameters sent to current activity.
Remove notifiers we cannot use.
Styling fixes for sync tables.
