AUI-1111 - AUI Diagram Builder nodes cannot be deleted

Hey @marclundgren,

Attached is an update for http://issues.liferay.com/browse/AUI-1111.  There is a Javascript error that gets thrown when you delete a node.  

![screen-capture](https://f.cloud.github.com/assets/860951/1872475/e44a12e2-78a6-11e3-91c6-94b67339c238.png)

Can you take a look and resend a new pull for this issue?  Please let me know if you have any questions.  Thanks!