Fixed issue #7315: Validation regex not being checked / not working (logic test ok) in preview mode
Fixed issue: Can not test group if token exist or if survey is not started
New feature: can use SGQA identifier to prefill some answer with URL in preview mode
Dev: add LimeExpressionManager->$sPreviewMode to be used and test if we are in preview mode
Dev: add LimeExpressionManager::SetPreviewMode public function to set previewmode