This is a crude wrapper around git diff for use with Scrivener.
If you're using git to track changes to a Scrivener document you
can use git log to get a list of changes. Each change is identified
by a long hex number.
You can then use scrivgit <that long hex number> to show the changes
between that checkin and the current state. It will show all the
scrivener pages that have changed, and for each page show a diff
of the rtf format of the document. You have to be inside the scrivener
document directory, i.e. inside the Whatever.scriv directory.
It's a very crude wrapper around git diff and you can pass it
versions to compare in the same way. scrivgit will show changes
since the last checkin and so on.