Remove unused local typedef

Patch by Andreas Lauser.  Thanks!

[[Imported from SVN: r7076]]

COPYING

@@ -17,7 +17,7 @@ Copyright holders:
 2009          Leonard Kern
 2005--2007    Sreejith Pulloor Kuttanikkad
 2003--2012    Robert Klöfkorn
-2010--2012    Andreas Lauser
+2010--2013    Andreas Lauser
 2007--2011    Sven Marnach
 2012          Tobias Malkmus
 2010          Rene Milk

dune/common/arraylist.hh

@@ -560,9 +560,6 @@ namespace Dune
       // Number of chunks with entries in it;
       size_t chunks = ((start_%chunkSize_ + size_)/chunkSize_ );
 
-      typedef typename std::vector<shared_ptr<array<MemberType,
-                  chunkSize_> > >::iterator iterator;
-
       // Copy chunks to the left.
       std::copy(chunks_.begin()+distance,
                 chunks_.begin()+(distance+chunks), chunks_.begin());