Fix for missing C++ code in std::multimap wrappers.

%template for a std::multimap generated uncompilable code unless a
%template for a std::map of the same template types was also coded up.

This patch is needed in conjunction with previous commit - 5f1fff1849

Closes #64
Closes #65

Examples/test-suite/li_std_multimap.i

@@ -3,7 +3,6 @@
 %feature("trackobjects");
 
 %include std_pair.i
-%include std_map.i
 %include std_multimap.i
 
 %inline %{
@@ -20,6 +19,5 @@ struct A{
 namespace std
 {
   %template(pairA) pair<int, A*>;
-  %template(mapA) map<int, A*>;
   %template(multimapA) multimap<int, A*>;
 }