Merge pull request
#1335 from ellisonbg/nbtoolbar...
Merge pull request
#1335 from ellisonbg/nbtoolbar
Add a toolbar with icons to the notebook interface. There are for now icons for the most important actions, we will slowly consider the addition of new ones later as necessary. But this should make everyday usage much more fluid for mouse-based users.
The new toolbar and the header bar have also been made collapsible, which allows users to have a very compact view with only minimal vertical space devoted to the UI and most of the screen available as usable work space.
