FieldMatrix<1,1> not explicit

[[Imported from SVN: r5609]]

common/fmatrix.hh

@@ -943,7 +943,7 @@ namespace Dune {
 
     /** \brief Constructor initializing the whole matrix with a scalar
      */
-    explicit FieldMatrix (const K& k)
+    FieldMatrix (const K& k)
     {
       a = k;
     }