Rename 'name' to 'variable' on the form designer
Fix validation error display on ticket open
Warn if leaving unsaved sorting preferences
Required 'name' if 'required' is set

If a form field is required, then a name will be necessary in order to plumb
up the API.
Merge pull request #84 from greezybacon/issue/form-issues

Corrects various form designer issues

Reviewed-By: Peter Rotich <peter@osticket.com>