Add an include in limit_reference.h
Add an include in limit_reference.h

* sigc++/macros/limit_reference.h.m4: limit_reference.h must include
visit_each.h, with the primary definition of template struct visitor.
https://mail.gnome.org/archives/libsigc-list/2014-August/msg00001.html

Distrotech/libsigcxx2,Distrotech/libsigcxx2,Distrotech/libsigcxx2