Decide regular release policy

[kentbull]

Feature request description/rationale

We should have regular releases based on a policy. This issue is a stub for the discussion on what that release policy should be. Once we, the community, have decided what that release policy is then this issue will be closed once we have a release policy written in docs/releases.md.

[iFergal]

For dev tags: I think something ad hoc like how it's done in keripy and KERIA make sense to me, at least right now. That way there isn't a flood of tags (e.g. release per PR merge) and people aren't forced to wait for a new release that's on a schedule. I haven't been requesting releases because npm is building from githash for me but I need to change that now.

For non dev tags, we should have a compatibility matrix with KERI.

A bigger discussion might be the actual versioning itself, semantic or something would be good.