Added the type block_type to DiscFuncArray to make it resemble an ISTL

class at least a tiny bit.

WARNING:  This will not work for vector-valued DiscFuncArrays.  I
didn't know how to do that correctly.

[[Imported from SVN: r1971]]

fem/discfuncarray.hh

@@ -45,6 +45,10 @@ namespace Dune {
 
     //! Type of the range field
     typedef typename DiscreteFunctionSpaceType::RangeField RangeFieldType;
+
+    /** \brief For ISTL-compatibility */
+    typedef FieldVector<RangeFieldType,1> block_type;
+
     //! Type of the grid
     typedef typename DiscreteFunctionSpaceType::GridType GridType;