Improve error message of `_handle_method_context`
Add syntax checking for A_Email attributes
Change to use `passlib` instead of `bcrypt`

Use `hash_cmp` to `verify`
Clear permissions for `group` and `other`

The session files *should not* be readable writable by `group` and `other`!
Fix spurious errors from _GTW.__test__.RST

* Add a sleep to `rst_harness.run_server` to avoid intermittent
  socket/protocol errors

* Fix `TFL.Q_Result_Composite.limit` (change from
  `@super_ordered_delegate` to `@super_ordered`)
Add `REST authorization token`

* refactor the `GTW.RST.Request` and `.Response` classes

* factor `hashlib` and `base64.encode` calls

* rename `login_required` to `auth_required` and move it up to
  `GTW.RST.Resource.Base`