[sigc] CMake files for libsigc++2.0.18

["R. Douglas Barbieri" <dooglio gmail com>]

Hi all,

As Murray asked me to do, I have created a bug in the buzilla db for a
feature request:

https://bugzilla.gnome.org/show_bug.cgi?id=599709

The tarball for cmake files is attached. I hope I was thorough
enough--please advise me if I goofed (this is my first time doing
this). :-)
-- 
Doug Barbieri
http://www.slitechat.org/