Domain wall fermions now invert ; have the basis set up for

Tanh/Zolo * (Cayley/PartFrac/ContFrac) * (Mobius/Shamir/Wilson)
Approx        Representation               Kernel.

All are done with space-time taking part in checkerboarding, Ls uncheckerboarded

Have only so far tested the Domain Wall limit of mobius, and at that only checked
that it
i)  Inverts
ii) 5dim DW == Ls copies of 4dim D2
iii) MeeInv Mee == 1
iv) Meo+Mee+Moe+Moo == M unprec.
v) MpcDagMpc is hermitan
vi) Mdag is the adjoint of M between stochastic vectors.

That said, the RB schur solve, RB MpcDagMpc solve, Unprec solve
all converge and the true residual becomes small; so pretty good tests.

lib/qcd/action/fermion/PartialFractionFermion5D.h

@@ -0,0 +1,49 @@
+#ifndef  GRID_QCD_PARTIAL_FRACTION_H
+#define  GRID_QCD_PARTIAL_FRACTION_H
+
+namespace Grid {
+
+  namespace QCD {
+
+    class PartialFractionFermion5D : public WilsonFermion5D
+    {
+    public:
+
+      // override multiply
+      virtual RealD  M    (const LatticeFermion &in, LatticeFermion &out);
+      virtual RealD  Mdag (const LatticeFermion &in, LatticeFermion &out);
+
+      // half checkerboard operaions
+      virtual void   Meooe       (const LatticeFermion &in, LatticeFermion &out);
+      virtual void   MeooeDag    (const LatticeFermion &in, LatticeFermion &out);
+      virtual void   Mooee       (const LatticeFermion &in, LatticeFermion &out);
+      virtual void   MooeeDag    (const LatticeFermion &in, LatticeFermion &out);
+      virtual void   MooeeInv    (const LatticeFermion &in, LatticeFermion &out);
+      virtual void   MooeeInvDag (const LatticeFermion &in, LatticeFermion &out);
+
+    private:
+
+      virtual void PartialFractionCoefficients(void);
+
+      zolotarev_data *zdata;
+
+      // Part frac
+      double R=(1+this->mass)/(1-this->mass);
+      std::vector<double> p; 
+      std::vector<double> q;
+
+      // Constructors
+      PartialFractionFermion5D(LatticeGaugeField &_Umu,
+				    GridCartesian         &FiveDimGrid,
+				    GridRedBlackCartesian &FiveDimRedBlackGrid,
+				    GridCartesian         &FourDimGrid,
+				    GridRedBlackCartesian &FourDimRedBlackGrid,
+				    RealD _mass,RealD M5);
+
+    };
+
+
+  }
+}
+
+#endif