#36

I've wanted to take care of : https://github.com/RisingOak/jenkins-client/issues/36. But at the same time I've runned across multiple problems with the testing in the project.

So.. initially and long story short I've:
- bumped up some versions of used libraries
- cleaned up the testing approach:
-- IntegrationTests are being executed by failsafe
-- unit tests are being executed by surefire
-- all tests pass and have meaningfull description and assertions
- updated README.md as well

As it comes, to the problem itself we can provide an easy fix on that, I've left it not fixed so far, waiting for your response (https://github.com/RisingOak/jenkins-client/issues/36).