moved username & centre param handing to session; simplifed separate db calls to single model() function; app_version git log function; merged Ajax class _get_referral_sources() with autosuggest_location route
moved get_pds_data() block to Role::PDS - don't need 'with' followed by 'with' any more in Validate; made logo img-responsive class to enable dynamic resize; tt layout rearrangements
