Change Console shortcut to create new node (Ctrl-N)

The console has the keyboard short Ctrl+N to create a new node. However, Ctrl+N often opens a new browser window (in Firefox on Linux) or tab (in Chrome on Linux). So the shortcut is effectively useless in these browsers. We should add an addition shortcut for creating a new node that also works in these browsers.

Since creating nodes is such a core task in the Console, it's very unfortunate that there's no working keyboard shortcut.