[SECURITY] Fedora 15 Update: libpng-1.2.46-1.fc15

The libpng package contains a library of functions for creating and manipulating PNG (Portable Network Graphics) image format files. PNG is a bit-mapped graphics format similar to the GIF format. PNG was created to replace the GIF format, since GIF uses a patented data compression algorithm. Libpng should be installed if you need to manipulate PNG format image files.