Wikia/mercury — pull request #326 by rogatty (2014-11-03 16:23:08+00:00)
Title: Clean before building for tests

I had to remove `/www` manually because `npm run test` was showing a lot of errors, for example:
```
PhantomJS 1.9.8 (Linux) ERROR
TypeError: 'undefined' is not an object (evaluating 'M.provide')
at /home/igor/workspace/mercury/test/helpers/baseline.js:8
```

Now it's automated.