Copied, renamed and adapted additional spring-test sources in order to
remove the library from compile time dependencies.
The spring-test source copies have been refactored in a grails-jaxrs
specific namespace, just to avoid incompatibilities with code that still
depends at runtime on spring-test (see
https://github.com/krasserm/grails-jaxrs/pull/24 ).
Adding some files just copied from spring-test (I missed to add in the
the previous commit)
Merged springtest_dep_removal in order to move springtest source copies under a dedicated namespace. This should make grails-jaxrs compatible with other code that depends on springtest at runtime, like the Mail plugin (grails-jaxrs does not have such runtime dep), at the cost of copying some springtest source contents under our codebase (I see no license compatibility issues).