Improved validateUserOrAdminLogin() in GanymedeServer

Put back in the check to make sure that a user persona
doesn't allow a login if the associated user is inactivated.

Put a check in to make sure that the monitor account isn't
allowed for login to create a GanymedeSession.
Cleaned up adminPersonaCustom.consistencyCheck()

A little parameterization of Vectors, some reformatting.

No semantic changes.
Clarified the javadoc header for GanymedeServer.validateUserOrAdminLogin()
Re-enable monitor login for read-only client use