Keep node_modules/vendor

It's a useful place to stick things as we modify them to be
browserifyable when patching upstream isn't an option.
Convert designer/js/utils to commonjs

* converted the utils lib to commonjs module format from requirejs.
* replaced the implementation of `getQueryStringVariable` with a version
based on `querystring` from the node standard library.
* started a test suite.
Convert designer/js/togetherjs to commonjs
Fix leaky variable, typo'd variable name.
Convert designer/js/publishPane
Convert designer/js/editable
Convert designer/js/keyboard
Convert designer/js/modes
Convert designer/js/debugger
Convert designer/js/click