Enable events to be badged.

Enable events to be badged.

Adds the "badged" flag to the Event model in order to distinguish
community badged events from other PostgreSQL oriented events.
Seven total events will be displayed on the homepage, with up to
four community events displayed. If there are no upcoming
community events then, then the header "Events" is shown.

The event submission interface allows a user to opt-in to
listing an event as a "community" event and provide an
explanation for moderators as to why the event should be
considered a community event.

Expands the list of News and Planet PostgreSQL blog entries to 10.