Added potential fix for https://www.pivotaltracker.com/story/show/64655000 (Patients can be created without an OpenMRS ID)
Updated patient_id_fixes.groovy to explicitly call savePatientIdentifier
Added new update component to fix missing OpenMRS IDs
Updated FixMissingOpenmrsIdentifiers chores to work with latest changes in kenyacore
Improved NotOnArtCalculation to stop loading patient observations individually so that it is more efficient. PT Story: https://www.pivotaltracker.com/story/show/64215706