Adds User Invites to Hub Docs

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)

(cherry picked from commit bf05f78d700532bb7504a2e1fd388f81c48aa2e6)
Include fred's release notes for 1.4.0.

He is unfortunately out of power and internet because of storms :(

Docker-DCO-1.1-Signed-off-by: Fred Lifton <fred.lifton@docker.com> (github: fredlf)
Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: jfrazelle)

(cherry picked from commit a65396b079c1b05255553af8cde3a94d7796e752)

Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: fredlf)
Merge pull request #9640 from fredlf/post-1.4.0-docs-update-1

Post 1.4.0 docs update 1