Add `_auto_headers` with `X-Frame-Options`
Add `-summary` to be compatible with `run_doctest`
Improve output of GTW.RST.TOP.MOM.Doc

* include query attributes

* always include `is_changeable`

* include `is_settable`

* hide associations with more than one role (they are accessible wvia
  their role types anyway)
Put `receiver`, `subject` in `defaults`

To allow the `msg` used for forward/reply/resend to override `receiver`
and or `subject`.
Add `server.terminate` to `reset_callbacks`