Allow HTML content as node label

[antiguru]

Hi there-
First of all, I would like to thank you for providing this library, it just fits my needs perfectly! Switching to dagre from a not-so-complete d3 layout took less than an hour!

In order to support actions when clicking on nodes it would be great if I could attach html content or a callback function to nodes, something like:

dagre.nodeOnClick(myCallback);
// later:
function myCallback(target) {...}

Allowing HTML content in the SVG could be used to provide the same functionality.

Thanks a lot,
Moritz

[antiguru]

Duplicate of #19.

[cpettitt]

As you saw, @robopeter recently submitted a patch with HTML support. I've updated the hosted demo to include his patch. Here's a quick example with an onclick handler.

His patch currently resides on the v0.0.3 branch. I plan to get this merged to master and published sometime this week.