[upstream] Update to ffmpeg-2.5.1.
[upstream] Update to harfbuzz-0.9.37.
[upstream] Update to cmake-3.1.0.
[upstream] Update to dhcpcd-6.6.6.
[upstream] VLC-2.1.5, libdvdcss-1.3.0, Libdvdread-5.0.0, Libdvdnav-5.0.1: fix download URLs.