Add uninstall target to Makefile

[0x09]

Hi, thanks for the awesome library.

This adds a make uninstall target that can be used to uninstall the libraries, utf8proc header, and pkg-config file.

An uninstall target would be useful for hfsfuse which bundles utf8proc as a subtree and offers the ability to uninstall bundled libraries in its own Makefile.

[stevengj]

Thanks! It would be good to add a test for this — i.e. do a make install into a temporary directory, then make uninstall, and check that it is empty (except for empty subdirs like lib and include).

[0x09]

Sure, let me know if something like this is what you had in mind, if so I'll add it to the tests dir and to make check.

#!/usr/bin/env bash

install_dir=$(mktemp -d)

if ! make install DESTDIR="$install_dir" ||
   [ ! -f "$install_dir/usr/local/include/utf8proc.h" ] ||
   [ ! -f "$install_dir/usr/local/lib/libutf8proc.a" ] ||
   [ ! -f "$install_dir/usr/local/lib/pkgconfig/libutf8proc.pc" ]; then
	echo "FAILED: make install" >&2
	rm -rf "$install_dir"
	exit 1
fi

if ! make uninstall DESTDIR="$install_dir" ||
   [ -n "$(find "$install_dir/usr/local/include" -type f )" ]; then
	echo "FAILED: make uninstall" >&2
	rm -rf "$install_dir"
	exit 1
fi

[stevengj]

Overall that looks good. For the make install test it would be good to check against the MANIFEST file.

I would also probably just rely on #!/usr/bin/sh rather than bash.

[0x09]

A minor issue with using the manifest as-is is that it doesn't take into account platform differences in the shared library name, so make check fails on macOS.
What we could do is have the test/install_uninstall target depend on the manifest target, and then reference Manifest.new in the test. This requires FIND be set to gfind on macOS due to the find syntax used when building the new manifest.
Since the Makefile already does platform detection for the shared library name and requires GNU find, it seems reasonable to just set FIND to this conditionally in the Makefile as well.

This seems like a reasonable solution to me so I'll push a new commit with these changes, but let me know if you know of a better way to do this.

[0x09]

The branch has been updated with the above changes.

[0x09]

@stevengj let me know if there's anything else to do here.