More Cities.md notes
Replace Geofences monitor with new fences

refs #4
Avoid reloading stations if we have recent data.

This should considerably reduce the number of requests sent when scrolling rapidly on a zoomed city.
NSLog -> DebugLog
remove the "monitored" attribute from the geofences

refs #4
Fix fences incorrectly being removed

refs #4
Tweak fences overlay style

refs #4
Increase the "star" button size

refs #4
Correct error message when adding a geofence fails.

fixes #4