This library was causing numerous issues related to git operations. The
straw that broke the camel's back is that it does not do automatic
garbage collection (`git gc --auto`). So a user's repo directory
continues to grow in size.
The replacement is CliWrap, which is just a simple wrapper library that
allows easy execution of shell commands. Specifically, `git` commands.
BREAKING CHANGE: This change now requires the `git` executable to be
installed by the user if run on a host system. The git executable will
be provided automatically for the docker image.
Robert Dailey