Resurrected @gchatelet's STL branch

Author: TurkeyMan

src/core/stdcpp/allocator.d

@@ -17,4 +17,4 @@ extern(C++, std):
  * Allocators are classes that define memory models to be used by some parts of
  * the C++ Standard Library, and most specifically, by STL containers.
  */
-struct allocator(T) { }
+extern(C++, class) struct allocator(T) { }