Allow new user default view templates to be edited (Bug #1303551)

- Adds template views to top of Pages list under Configure site menu
- Profile, dashboard and group homepage templates can be edited.
- Only layout and content can be edited.
- Templates are only applied to users and groups created after changes are made.

Change-Id: I35967950a37887b31595a4afbc19300dd070949f
Signed-off-by: Nathan Lewis <nathan.lewis@totaralms.com>
Merge "Allow new user default view templates to be edited (Bug #1303551)"