fr8x-editor: some cleanup.

Hi Mark,

I cleaned some things up:

* Replace ``Your name.`` with "your name". :-)

* ``ERROR: foo desc`` automatically make a ``foo`` throwing constructor.

* Replace ``1 swap nth`` with ``second``.

* Fixed error in the ``register-select`` button where the stack effect is wrong because you weren't dropping the button gadget.

* Fixed ``show-drop-menu``, not really sure what it is supposed to do, but it "works" now.