Merge pull request #42 from BoykoAlex/master

Robustness for GroovyCompilationUnitTests#testGetModuleNode_7()
Groovy 2.3.0
ClassPath update for Groovy 2.3 (used to be rc2)
Tests robustness fix. Compare initial size of the cache with the final
instead of checking whether it's completely empty to account for tests
that may leave the cache not empty