The changelog does not seem to have a RSS feed.
You could use GitHub releases when new stable releases are made. It would make it easy for users to subscribe to something to get notified of new releases of SCEPman and Certificate Master.
Idea:
- Separate releases for Certificate Master and SCEPman.
- Include changelog for the released version only in GitHub releases.
I'm not currently aware of other ways to get notified of new releases.