case of zero entry pressure added in regularization of dSw/dpc function

git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@5114 2fb0f335-1f38-0410-981e-8018bf24f1b0

dumux/material/fluidmatrixinteractions/2p/regularizedbrookscorey.hh

@@ -203,6 +203,12 @@ public:
     {
         const Scalar Sthres = params.thresholdSw();
 
+        //instead of return value = inf, return a very large number
+        if (params.pe() == 0.0)
+        {
+            return 1e100;
+        }
+
         // calculate the saturation which corresponds to the
         // saturation in the non-regularized version of the
         // Brooks-Corey law