git diff format support

Hello again,

I am struggling with "svn diff" output format, which doesn't contain
information about added, copied and renamed files. This information is
needed for generating complete code review diffs for Rietveld project.
It would be nice if `svn diff` supported additional -g, --git option
to generate output that contains this info -
http://mercurial.selenic.com/wiki/GitExtendedDiffFormat

Please, CC.

--
anatoly t.