DATACMNS-391 - Ensure compatibility with Spring Framework 4.0.0.X.

Some tests required an explicit dependency to servlet-api-3.x.
The GenericApplicationContext doesn't refresh automatically in Spring 4.x we thus we have to call refresh manually. Added a specific version of populators.xml for Spring 4.x since the jaxb2-marshaller element definition no longer renamed the contextPath attribute to context-path in 4.x.