Add special "Start" button to Enrollment Flow views (CFM-428) (COmana…

…ge#251)

* Add special "Start" and "Copy" (flow url) buttons to Enrollment Flow configuration views (CFM-428)

* Improve "Cannot copy" message for javascript clipboard (CFM-428)

* Make upper buttons more generic (CFM-428)

* Shorten test block for applying upper buttons (CFM-428)

* De-emphasize "Copy URL" and move it to the left of "Start" (CFM-428)

* Remove "Copy URL" button (CFM-428)

* Trivial clean up to comment (CFM-428)