[libsigcplusplus] limit_trackable_target: =delete copy/move operations.

[Murray Cumming <murrayc src gnome org>]

commit 3c2461195d8dafd25d6fb389dbc20079e58ac6f0
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Apr 15 20:34:44 2016 +0200

    limit_trackable_target: =delete copy/move operations.

 sigc++/visit_each.h |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/sigc++/visit_each.h b/sigc++/visit_each.h
index 2fc6ad7..99039f4 100644
--- a/sigc++/visit_each.h
+++ b/sigc++/visit_each.h
@@ -50,6 +50,11 @@ struct limit_trackable_target
 
   explicit limit_trackable_target(const T_action& _A_action) : action_(_A_action) {}
 
+  limit_trackable_target(const limit_trackable_target& src) = delete;
+  limit_trackable_target& operator=(const limit_trackable_target& src) = delete;
+  limit_trackable_target(limit_trackable_target&& src) = delete;
+  limit_trackable_target& operator=(limit_trackable_target&& src) = delete;
+
   T_action action_;
 
 private: