Update CHANGLOG format headings for Vandamme/Gemnasium compatability.
Update CHANGLOG format headings for Vandamme/Gemnasium compatability.

A common CHANGELOG format is great, welcome news. Consider updating your
CHANGLOG to match as well! For more details, see:

https://github.com/tech-angels/vandamme#changelogs-convention

fnichol/knife-server,fnichol/knife-server