Comment 12 for bug 1325777

@Angel,
I'm sure the design team will add, but my comments are as follows:
* I can't resize the window
    * This would be a good option to allow a scientific mode, which has sin, cos, tan etc.
* I can't see what I typed, nor history
* Use a headerbar, even if it only has the title (like Pantheon Photos and Pantheon Terminal)
* The undo shouldn't be as is---replace with back/forward in history

Optional:
* Instant results that don't display errors until enter/= is pressed