Cow should update Included module versions table in changelog

[GuySartorelli]

The changelog includes a table listing module versions: "Included module versions". This is currently hardcoded modules in the changelog template which need to be updated manually. This is something cow should handle for us.

Acceptance Criteria

• When generating changelogs, cow adds all of the modules being released to the module versions table
• When generating changelogs, cow sets the correct version for all modules in the module versions table