Fix bug in func test helper
Fix bug in func test helper

Would exit(2) and end test run when given a bad command line option.

little-dude/nose2,ojengwa/nose2,ptthiem/nose2,ojengwa/nose2,leth/nose2,ezigman/nose2,ezigman/nose2,ptthiem/nose2,little-dude/nose2,leth/nose2