* file: update from 5.29 to 5.30
* ffmpeg: update from 3.2.2 to 3.2.4
* mpv: update from 0.23.0 to 0.24.0
also prevent opportunistic linking with x11
* grep: update from 2.28 to 3.0
* fish: update from 2.4.0 to 2.5.0
add tarball checksum
remove patches no longer needed
see https://github.com/fish-shell/fish-shell/pull/3585
* wget: update from 1.19 to 1.19.1
Let build-package.sh setup the $PREFIX/lib/libstdc++.so symlink
before building any package, to make sure that all C++ applications
link against a fully featured C++ standard library.
Avoid explicitly declaring a dependency on the libgnustl package
since everyone may link against it at will and instead mark it as
essential.
