Merge pull request #28 from shishlo/development

The #26 is fixed.

src/mpi/wrap_mpi_comm.cc

@@ -162,6 +162,7 @@ extern "C" {
 	pyORBIT_MPI_Comm* newMPI_Comm(){
 		pyORBIT_MPI_Comm* pyMPI_Comm = PyObject_New(pyORBIT_MPI_Comm,&pyORBIT_MPI_Comm_Type);
 		pyMPI_Comm->comm = MPI_COMM_WORLD;
+		Py_INCREF((PyObject *) pyMPI_Comm);
 		return pyMPI_Comm;
 	}