Tests for all NodeStream features

We need tests for NodeStream to be able to ensure the quality of the product. The idea is to:

• Create tests for all features included in NodStream
• Create tests for functionality provided in NS Core

Collaborative work is going on in this sandbox: http://drupal.org/sandbox/fabsor/1435136 , Ping fabsor or balintk in #nodestream to get access. We split each issue up into a specific branch for easy inclusion into NodeStream.

This is a meta issue, and the idea is to have an issue for each feature that we need tests for. Current issues are:

#1404904: Tests for NS Article
#1435216: Create a good base test case for testing content provider features