Tag ink! crates with 2.0.0 release (#353)

* [*] initial swipe over codebase to tag 2.0.0 release

* [*] fix a number of issues with the previous version setup
1 job for latest-v2 in 1 minute and 22 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Publish
passed #421734
linux-docker
publish-docs

00:01:22