Create fix for paths that contain spaces

Paths that contain spaces caused grunt-scss-lint to incorrectly report that all files are lint free.

This commit/pull request fixes that.

Also:
- Added tests for spaces in paths
- Made tests more sturdy
- Made tests compatible with latest version of scss-lint
- Incremented version number from 0.3.3 to 0.3.4
No I put it there for a reason. The test would fail but not in a very nice matter. It would throw an error `Cannot call method 'indexOf' of undefined` instead of displaying a more human readable result like was intended. At least that's what happened on my local machine with my node version.