Include release notes

[RacingTadpole]

Is there a list of what's changed between releases of python-jose?

I'm having trouble deciding when a new version of python-jose is crucial – eg. because it includes security patches or fixes a bug that could affect my usage – vs when it is just a nice-to-have. Unfortunately redeploying is not always costless.

A change log / release notes would really help with this - or if you already have one, a link to it in the read-me or docs.

Thanks!

[blag]

Closed by #132.