Update to 2.56. From the changelog:

* autoindex: New plugin that generates missing index pages. (Sponsored
    by The TOVA Company.)
* Escape HTML is rss and atom feeds instead of respectively using
    CDATA and treating it as XHTML. This avoids problems with
    escaping the end of the CDATA when the htmlscrubber is not used,
    and it avoids problems with atom XHTML using named entity
    references that are not in the atom DTD. (Simon McVittie)
* Add test for old versions of git that don't support --cleanup=verbatim,
    and munge empty commit messages.

(schmonz)