DB\IO Tester now has correct testing for pgVersion string compare. Uses
mocked pgVersion return for this
Session class update with full magic set/get or method set/get for
_SESSION var. Also added full testing for this
All static Session:: calls (except for checking valid session name) are
converted to object type. This Object is passed on to Login, Admin
Backend and any other class that needs basic session checking
Add a write close session call to end a session for AJAX calls
Add error strings to session start method
Add check call for session names that they are valid
