gitstats does not currently need to be installed; it's used right from the
directory (it also assumes some files like the stylesheet are in .)

Suppose you have a git project at /mnt/src/git/project
and you want to save the statistics to ~/public_html/project

You would run:
$ ./gitstats /mnt/src/git/project ~/public_html/project
(go grab a cup of coffee if it's a large project :)
$ sensible-browser ~/public_html/project/index.html