Add class to test the preview controller
Add @see for controller class
Add tests to check the preview controller and route
Merge branch '8.x-1.x' into preview-tests
Enable editor module since the preview route has it as dependency
Use proper GET attributes while passing value
Use strip_tags() instead of rewriting placeholder
Add period at the end of comment as per coding standards
Merge pull request #59 from cs-shadow/preview-tests

Add tests to ensure preview route/controller is working correctly