[libsigc++2] type_traits.h: Remove the unused type and pointer types.

[Murray Cumming <murrayc src gnome org>]

commit 6e7daa879d6e6e53639d8ad4762d0cbd45dd1f57
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Aug 13 11:36:00 2015 +0200

    type_traits.h: Remove the unused type and pointer types.
    
    These were apparently never used.
    Bug #753580

 sigc++/type_traits.h |   10 ----------
 1 files changed, 0 insertions(+), 10 deletions(-)
---
diff --git a/sigc++/type_traits.h b/sigc++/type_traits.h
index 665a1d0..a4989f0 100644
--- a/sigc++/type_traits.h
+++ b/sigc++/type_traits.h
@@ -27,46 +27,36 @@ namespace sigc {
 template <class T_type>
 struct type_trait
 {
-  typedef T_type  type;
   typedef T_type& pass;
   typedef const T_type& take;
-  typedef T_type* pointer;
 };
 
 template <class T_type, int N>
 struct type_trait<T_type[N]>
 {
-  typedef T_type*  type;
   typedef T_type*& pass;
   typedef const T_type*& take;
-  typedef T_type** pointer;
 };
 
 template <class T_type>
 struct type_trait<T_type&>
 {
-  typedef T_type  type;
   typedef T_type& pass;
   typedef T_type& take;
-  typedef T_type* pointer;
 };
 
 template <class T_type>
 struct type_trait<const T_type&>
 {
-  typedef const T_type  type;
   typedef const T_type& pass;
   typedef const T_type& take;
-  typedef const T_type* pointer;
 };
 
 template<>
 struct type_trait<void>
 {
-  typedef void  type;
   typedef void  pass;
   typedef void  take;
-  typedef void* pointer;
 };
 
 template<typename T>