What's new since 0.5.1?

• Updated git to 2.22.0 for the helper.
• cinnabarclone support is now enabled by default. See details in README.md and mercurial/cinnabarclone.py.
• cinnabarclone now supports grafted repositories.
• git cinnabar fsck now does incremental checks against last known good state.
• Avoid git cinnabar sometimes thinking the helper is not up-to-date when it is.
• Removing bookmarks on a Mercurial server is now working properly.