Replace var_export with print_r. var_export can't handle circular references - ends in fatal error. Thus imposible to use objects with circular dependencies in mock params

(cherry picked from commit 6b4a6cfe06d61df65da61829f1609b1e137c7f77)
Merge branch 'feature/mockregistry' into mymaster

* feature/mockregistry:
  Mock->mockName changed to Mock->getMockName()
  Registry - ability create and retrieve named mocks.