MILYN-658 - Groovy upgrade

Pull request for groovy upgrade - still the issue with not passing test is not resolved #57 

Root cause of the issue is the size of the ml tag value - if the value is to long end of the value is added twice - probably wrongly parsed by the xerces ( https://gist.github.com/hicolour/801ecc7f14f124c2e7f6#file-smooks-xerces )

junit.framework.ComparisonFailure: expected:<...em>Luxury Helicopter[]</item>
        <ite...> but was:<...em>Luxury Helicopter[ter]</item>

Definitely issue is not caused by groovy upgrade -  output of the groovy script is correct.

To show nutshell of the issue test was split into failing and not failing case.