Integration tests need to be more specific

[pettermahlen]

The current set of integration tests (previous system tests) don't necessarily find the right bugs. We should probably add functionality along the following lines:

• verify for each system test that its unit tests work (these tests verify that there are in fact errors in the code)
• modify the plugin to enable computer-parseable output in addition to the human-readable output
• modify the integration tests to verify that the 'correct' error is found for each test case, based on the computer-parseable output.