Merge pull request #361 in ZP/z-push from bugfix/ZP-1013-ios-does-not-send-meeting-response to develop

* commit 'ca2145a5':
  ZP-1013 modified regexp for getting iOS user agent.
  ZP-1013 Uppercase hex globalobjid for iOS devices and Outlook.
  ZP-1013 iOS does not send meeting response.