Add Shift Manager

This change adds the shift manager singleton which is used to preserve state between application restarts.

Added PPRShiftManager
Added PPRShiftManagerTests
Modified PPRTestIntialiser to use shift manager
Modified PPRShiftViewController to move the shift related “key” strings to the new PPRShiftManager.
Fix a bug on a test case.
Merging Pods configuration.
Merge branch 'shift_manager'
Merge of fix of merge of project settings.