Log Message:
mktool: Update to 1.0.0.

This is the first official stable release, so take maintainership of the
package.  I'm now reasonably confident that the replacement utilities will
work correctly in all cases, backed up by a number of bulk builds and lots
of testing.

Changes since the last beta release are:

 * Much improved "mktool fetch" output.

 * Higher performance and lower system time by switching to rayon threads.

 * A number of minor cleanups.

Enjoy!