Enables the Standard suite of AppleScript commands

A user came to #textual today asking about [Layouts](http://projects.jga.me/layouts/) compatibility with Textual.
This uses a few of the window-related verbs in the Standard suite, but Textual was not enabled for even these rudimentary verbs.

Of course this does not allow for any Textual-specific AppleScript commands, but these window commands require no further changes to the code to enable some useful features.