Added CSS formatters (Less, Stylus, Plain CSS) to the example app generator (incl. tests). Fixed test environment.

Added CSS formatters (Less, Stylus, Plain CSS) to the example app generator, including tests.

The test Makefile has been fixed to be able to run tests. Compatible with *.coffee tests too (tested).

Tests have passed successfully:
![Tests passed](https://f.cloud.github.com/assets/722609/2018221/2ad14be6-880a-11e3-9a44-4697d8228f92.png)