JERSEY-1881: MoxyXmlFeature.classes / MoxyContextResolver.classes are not used to create JAXBContext

 - updated MoxyContextResolver
 - added test

Change-Id: I6e2f325860bedf55962e8646347ee60de6f89876
Merge "JERSEY-1881: MoxyXmlFeature.classes / MoxyContextResolver.classes are not used to create JAXBContext"