Resolve "Creating labs gives 500"
This mr does three things to the lab creation page mentioned in #102 (closed)
- The 500 error is gone by fixing a bug in the backend
- A form field is now properly aligned with the rest
- All validation also happens in the browser with a consistent api, rather than mixing backend / custom alerts and the browser constraint api.
See the individual commit messages for more info
This addresses some important issues from #102 (closed), but the entire story of validation is not entirely resolved. I think we should discuss our strategy regarding validation there.