Description of problem: Description of problem: Non-privileged user can start DataSource creation, but can not actually create a DataSource

Version-Release number of selected component (if applicable):

How reproducible: always

1. Log in as test/test
2. Open DataSource page
3. Click on "Create DataSource" button and select "With form"
4. Fill DataSource form and click "Create" button.

Actual results: Error message appears, the DataSource is not created

Expected results: "Create DataSource" button is disabled for non-privileged user, or whole DataSource page is hidden

Additional info: