message: fix ambiguous default parameter issue for the parallel builds
  Since MPI_Comm is an int type the compiler was getting confused when trying to compile the parallel unit tests. So, I just moved the double parameters before the int CGSolver parameters.
diff: @@ -39,12 +39,14 @@ protected:
  Vector m_all_data;
  BilinearForm *L2;
  CGSolver *cg;
  + FiniteElementSpace *fes;
  int NE;
  public:
  // The FiniteElementSpace passed into here should have a vdim set to 1 in order for the
  // MassIntegrator to work properly if the ProjectQuadratureCoefficient method is used with
  // a VectorQuadratureFunctionCoefficient.
  - FieldInterpolant(FiniteElementSpace *fes) : setup_disc(false), setup_full(false)
  + FieldInterpolant(FiniteElementSpace *fes) : setup_disc(false),
  + setup_full(false), fes(fes)
  {
  L2 = new BilinearForm(fes);
  @@ -83,8 +85,8 @@ public:
  L2->Update();
  L2->Assemble();
  }
  - virtual void SetupCG(int print_level = 0, int max_iter = 2000,
  - double rel_tol = 1e-15, double abs_tol = 0.0)
  + virtual void SetupCG(double rel_tol = 1e-15, double abs_tol = 0.0,
  + int print_level = 0, int max_iter = 2000)
  {
  cg = new CGSolver();
  cg->SetPrintLevel(print_level);
  @@ -138,8 +140,9 @@ public:
  }
  using FieldInterpolant::SetupCG;
  // Setup the CG solver with an MPI communicator
  - virtual void SetupCG(MPI_Comm _comm, int print_level = 0, int max_iter = 2000,
  - double rel_tol = 1e-15, double abs_tol = 0.0)
  + virtual void SetupCG(MPI_Comm _comm, double rel_tol = 1e-15,
  + double abs_tol = 0.0,
  + int print_level = 0, int max_iter = 2000)
  {
  cg = new CGSolver(_comm);
  cg->SetPrintLevel(print_level);
  