Merge pull request #5782 from alalek:update_libpng
authorVadim Pisarevsky <vadim.pisarevsky@gmail.com>
Fri, 11 Dec 2015 16:13:40 +0000 (16:13 +0000)
committerVadim Pisarevsky <vadim.pisarevsky@gmail.com>
Fri, 11 Dec 2015 16:13:40 +0000 (16:13 +0000)

Trivial merge