Shift state and Settings Tab

This change moves publishing of changes to currently selected facility to a shift object which is published with shift state and implement changing shift state.

The changes to shift state are persisted in user settings.

A settings tab is added to the user interface to allow uses to reset the stored user settings to defaults.

Add PPRShift object to hold shift state.

Modify PPRClientViewController change key for notification.

Modify PPRShiftViewController
- change the keys for facility id and add keys for shift
- refactor handling of change of facility to be part of shift.

Add PPRSettingsViewController to handle reseting shift state.

Add PPRSettingsNavigationController for future display of shift state in tab bar.

Modify Main,storyboard to add Settings tab.

Modify StringKeys.h to add user settings keys and shift change notification keys.
Add PPRStickyMessageNoticeView

The standard StickyNoticeView in the NoticeView “pod” does not display the notice view message. This is a clone of StickyNoticeView combined with the message display of ErrorNoticeView.
Add scheduler time simulation and settings controls.

This change adds to the scheduler the concept of scheduler time which can be used to test the scheduling of the application.
The scheduler time maintained by a one second timer. Each time the scheduler time is updates, a notification is posted.
The settings tab allows the time to be set and a “warp” factor which can be used to speed up the “clock”.

PPRClockTabBarItem has been added to display the scheduler time.
PPRSettingViewController has been modified to replace the “Settings” tab bar label with a ClockTabBarItem and register the clock display for update notification.
PPRScheduler is modified to manage the schedulerTime and provides routines to calculate the equivalent wall time clock value for a schedulerTime value.
PPRAppDelegate has been modified to start the scheduler timer and to post notifications when the schedulerTime has changed. Experimental NoticeView messages have been removed and a more generic display of notifications provided.
Main.storyboard has had controls added to control the schedulerTime.
Merge pull request #16 from davidbernard/clock_toolbar_item

Scheduler Time and associated controls and settings