qa_tests/risk:

Removed base class `test` methods so that nosetests doesn't get
confused when collecting tests. The presence of the base class
methods was causing risk qa tests to be included in nosetests'
test collection when `nosetests -a '!qa'` was explicitly used.
Merge pull request #1223 from larsbutler/fix-risk-qa-test-collection

Fix Risk QA test collection (nosetests)

[r=micheles] [f=*trivial]