Adjust exception message to new class name.

[[Imported from SVN: r12662]]

dune/fufem/assemblers/localassemblers/geomexactstvenantkirchhofffunctionalassembler.hh

@@ -156,7 +156,7 @@ public:
         configuration_ = dynamic_cast<GridFunction*>(newConfig);
 
         if (!configuration_)
-            DUNE_THROW(Dune::Exception,"In [GeomNonlinStVenantFunctionalAssembler]: GridFunction cast failed!");
+            DUNE_THROW(Dune::Exception,"In [GeomExactStVenantKirchhoffFunctionalAssembler]: GridFunction cast failed!");
     }
 
 protected: