Fix project dependencies
Add simple grid splitters to sidebar
Add save dialog to save buttons
Add highlight and mouseover effect to nodes
Clean up sidebar selected node info box
Add circle at end of connector line

This is a temporary guide to show the direction of the connection.
Will eventually replace with proper arrows.
Add delete keybinding and command plus general

input improvements.

* CTRL+click two nodes add/removes connections.
* SHIFT+click canvas adds new node
* DELETE key deletes selected node
Add help dialog with basic key bindings