v2.2.0 release notes missing some changes

[jamestelfer]

Ref: https://github.com/aws-cloudformation/cloudformation-cli-go-plugin/releases/tag/v2.2.0

In particular, it doesn't mention that this release includes #230.

Also, should the v2 release stream be marked as "latest" now? The v1 release appears on the homepage as the current release, and I'm pretty sure that is no longer working since go1.x has been deprecated.