Improve color validation

Check via regexp, handle non-strings gracefully.
Implement localStorage

Add filtered JSON writing and reading for JSON nodes.

Save to localStorage in a debounced (1sec) handler hanging
on componentDidUpdate.

Restore from localStorage if possible.

Add a "clear" function to the root element to quickly reset
the whole graph after confirmation.
Round node width

Don't do ugly subfraction widths.
Change document title according to root node

Make "MindMap: " followed by the root node name the current titleChange document title according to root node

Make "MindMap: " followed by the root node name the current title.
cleanup
IDEA files