track clicks on 'Add Number' in Edit Mobile Workers

waiting on confirmation that this is exactly what we want to track

https://docs.google.com/a/dimagi.com/spreadsheet/ccc?key=0Auf3SPj8OfXDdE5Ga0pTZnhDSDg5cVVhWXhtZF9ZeGc&usp=drive_web#gid=0