Adding MPIDimsCreateError exception.

src/TNL/Exceptions/MPIDimsCreateError.h

+/***************************************************************************
+                          MPIDimsCreateError.h  -  description
+                             -------------------
+    begin                : Jan 30, 2019
+    copyright            : (C) 2019 by Tomas Oberhuber et al.
+    email                : tomas.oberhuber@fjfi.cvut.cz
+ ***************************************************************************/
+
+/* See Copyright Notice in tnl/Copyright */
+
+#pragma once
+
+#include <stdexcept>
+
+namespace TNL {
+namespace Exceptions {
+
+struct MPIDimsCreateError
+   : public std::runtime_error
+{
+   MPIDimsCreateError()
+   : std::runtime_error( "The program tries to call MPI_Dims_create with wrong dimensions."
+                         "Non of the dimensions is zero and product of all dimensions does not fit with number of MPI processes." )
+   {}
+};
+
+} // namespace Exceptions
+} // namespace TNL