BUG: fix Java SWIG wrappers

* Fix segfault in Registry::CreateApplication, but still return an Application object, not Application_Pointer
  This is done by renaming the original Registry::CreateApplication method to Registry::CreateApplicationInternal,
  and then creating an artificial Registry::CreateApplication method in Java which calls CreateApplicationInternal,
  and then __deref__ on the result to get an Application object
* need to comment out %ignore itkClass##_Pointer so that Application_Pointer is wrapped
* add necessary typemaps (inspired from SWIG Java doc) for converting between C++ std::vector<std::string> to/from Java String[]