Update compressible flow solver for Parallel-in-time

Issue/feature addressed

The main feature of this MR is to update the compressible flow solver for Parareal.

Proposed solution

• Modification to CompressibleFlowSystemImplicit class to use m_comm->GetRowComm() instead of m_comm in the instantiation of the non-linear system object.
• Use of the GetSpaceComm() communicator, when relevant.

Implementation

Tests

Suggested reviewers

Please suggest any people who would be appropriate to review your code.

Notes

Please add any other information that could be useful for reviewers.

Checklist

• Functions and classes, or changes to them, are documented.
• [ ] User guide/documentation is updated.
• Changelog is updated.
• [ ] Suitable tests added for new functionality.
• Contributed code is correctly formatted. (See the contributing guidelines).
• [ ] License added to any new files.
• No extraneous files have been added (e.g. compiler output or test data files).

library/SolverUtils/Forcing/ForcingAbsorption.h

@@ -104,6 +104,7 @@ protected:
         const Array<OneD, Array<OneD, NekDouble>> &inarray,
         Array<OneD, Array<OneD, NekDouble>> &outarray,
         const NekDouble &time) override;
+
     SOLVER_UTILS_EXPORT virtual void v_ApplyCoeff(
         const Array<OneD, MultiRegions::ExpListSharedPtr> &fields,
         const Array<OneD, Array<OneD, NekDouble>> &inarray,
@@ -121,6 +122,4 @@ private:
 };
 } // namespace SolverUtils
 } // namespace Nektar
-// Hui XU  21 Jul 2013 Created
-// Yumnah Mohamied May 2014 Modified and generalised.
 #endif