SAK-19605 add a cancel button when adding or editing an email template


git-svn-id: https://source.sakaiproject.org/svn/emailtemplateservice/trunk@307419 66ffb92e-73f9-0310-93c1-f5514f145a0a
SAK-22657 only validate the key + locale when it is a new template


git-svn-id: https://source.sakaiproject.org/svn/emailtemplateservice/trunk@307420 66ffb92e-73f9-0310-93c1-f5514f145a0a