Improve concision, add rake tasks, more

Hey -- a decent bit going on in this one.

+ Renamed database fields to improve concision. To get an event's name, it's `event.name`, whereas before it was `event.event_name`.
+ Improved `db:populate` rake task to fill in more fields.
+ Added rake task to reset the database `db:reset` and to reset & repopulate the database `db:rp`
+ Declare single gem versions in `Gemfile`, to prevent future compatibility issues. Even minor point updates can screw things up.

It looks like this is also re-adding some stuff that Jos added via his last pull request (see `events_ctrl.js`, for example). This might have something to do with me selectively adding files into my local dev branch? Not clear on this.