Merge topic 'reimport-png'

42eb48a7 Merge branch 'upstream-png' into reimport-png
1699df8b png 2017-05-02 (7bd5d074)
497d16b0 png: import a readme for Kitware patches

Acked-by: Kitware Robot <kwrobot@kitware.com>
Reviewed-by: Brad King <brad.king@kitware.com>
Merge-request: !2760

ThirdParty/png/update.sh

@@ -20,6 +20,7 @@ CHANGES
 KNOWNBUG
 LICENSE
 README
+README.kitware.md
 TODO
 Y2KINFO
 

ThirdParty/png/vtkpng/README.kitware.md

+# PNG fork for VTK
+
+This branch contains changes required to embed PNG into VTK. This includes
+changes made primarily to the build system to allow it to be embedded into
+another source tree as well as a header to facilitate mangling of the symbols
+to avoid conflicts with other copies of the library within a single process.
+
+  * Add attributes to pass commit checks within VTK.
+  * Addition of a CMake build for building within VTK.
+  * Mangle all exported symbols to have a `vtk_png_` prefix.
+  * Support for using VTK's import of zlib.