Extract editor state for specs into module.
Move g class to body element.

So we can bind stuff to '.g workspace'.
Bindings for pane:show-{previous,next}-item.
Bind cmd-r to window:reload, use !important for our keymap selectors.

By default cmd-r is bound with '.platform-darwin .editor'. !important lets my
binding win. Using !important without .g does not seem to suffice.