Reposurgeon enables risky operations that version-control systems don't want
to let you do, such as editing past comments and metadata and removing
commits. It works with any version control system that can export and import
git fast-import streams, including git, hg, fossil, bzr, CVS and RCS. It can
also read Subversion dump files directly and can thus be used to script
production of very high-quality conversions from Subversion to any supported
DVCS.
