fixed build, refs #1

The project builds now fine with xtext 2.1:

![screen shot 2013-05-17 at 19 30 02](https://f.cloud.github.com/assets/185278/519429/8289b7cc-bf17-11e2-8510-70f5a04635e7.png)


If Nodeclipse/coffeescript-eclipse#4 is resolved, we can imho release `0.3`.