Fixed non-standard introspection support in LazyObject.

LazyObject called a public method ``get_all_members`` on wrapped objects in
order to allow introspection.  This could easily cause name clashes with
existing methods on wrapped objects, and so has been changed to use the
standard methods.  This could be slightly backwards-incompatible, in obscure
cases, if the undocumented LazyObject has been used externally.



git-svn-id: http://code.djangoproject.com/svn/django/trunk@11636 bcc190cf-cafb-0310-a4f2-bffc1f526a37