enable breakpoints in webapp ace editor

![screen shot 2014-11-24 at 12 43 30 am](https://cloud.githubusercontent.com/assets/5429146/5162341/01ed00c6-7373-11e4-919a-45efc9ea2756.png)

* webapp breakpoints are now working (only in the "free text" javascript ace editor).
* They can be created or removed by clicking on the line number gutter next to the code.

Issues:
* The breakpoints established in the ace editor will function properly while in blocks (droplet) mode, but you won't be able to see them or add/remove them.
* If you add/remove code in the editor, the breakpoints stay on the same lines numbers and do not "move" to follow the existing code.