patch for nested and auto-discovery of integration tests

I moved things around a little bit in the main method where tests are discovered and added to the testing queue, the behavior should be consistent and I have it running against the core maven its right now to validate..

basically, if you run the verifier without any arguments it will try and discover all unit tests in the current directory and down, if you put something on the argument line that isn't a #### or starting with 'it' then it will in turn try and discover tests in that directory...

it uses the latest FileUtils.getFiles() looking for the presence of a 'goals.txt' file since that is required to be a test in anyway... I also updated the FileUtils and its deps from the plexus-utils trunk (and added StringUtils for good measure)