List view is finally working like I want it to (I think).  w00t!

* All data is now kept in a shared ordered array: named regions, whether they are actively scanning or not, the CLBeaconRegion, their status (unknown, inside, outside), and the distance from the beacon
* The table view simply renders the shared ordered array (rather than keeping its own proxy of a subset of the data)
* Whenever there is a change, the controller tells the table view to re-render
The app seems to be working!

* You can start and stop scanning
* The second page shows the regions (that are currently hard-wired into the app) that we’re searching for
* If you enter any of the regions, a pair of ruby slippers shows up next to that region name
* If you tap any region name, it shows you the details of that region (whether you’re in or out of it, the uuid, last time it saw a beacon for that region, the major/minor for the beacon, etc.)

And it seems to detect the RPi beacon well.  Yay!  It seems to take about 30 seconds for iOS to decide that you are outside the region (e.g., if I shut off the beacon, iOS tells me that we’re “outside” the region about 30 seconds later).  This is fine for our purposes.
Merge remote-tracking branch 'origin/master'