Merge branch 'CRM-13014' of git://github.com/eileenmcnaughton/civicrm-core into pull-request-1139

Conflicts:
	CRM/Utils/System/Base.php
	CRM/Utils/System/Drupal.php
	CRM/Utils/System/Drupal6.php

Also: Update comments

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* CRM-13014: CiviMobile fatal on non-d7 -Need a UF function for login authenticate
  http://issues.civicrm.org/jira/browse/CRM-13014