GPII-559

Bound the "Save & Apply" button to the saveSettings method. This will both save to the preferences server and update the system via the logout - login mechanism used by the PMT. Currently web sockets are not being used, although the code was left behind in case we decide to move back to using it.

Note that this pull request replaces https://github.com/GPII/prefsEditors/pull/23

http://issues.gpii.net/browse/GPII-559