Improve notifications

[sjaustirni]

Various small fixes and enhancements:

• Automatically fetch new notifications from NEWS_FEED_ROUTE if NUM_NOTIFICATIONS_ROUTE returns notification count > 0. Previously it would only fetch the new notification on page load. The bug was introduced here.

• Show a loader while we are fetching notifications. Fixes #143 Desktop: Mobile:

  • The red dot indicator now disappears when the user opens the notification dropdown and it does not even appear if new notifications are fetched while the dropdown is open.

[CLAassistant]

All committers have signed the CLA.