Improve the Licensing documentation
Presently the email you get when receiving a License from GitLab directs you here: https://docs.gitlab.com/ee/user/admin_area/license.html
The general content is mostly fine, although it does not address CE to EE upgrades very well. This is as large, or larger, than net new customers. So it's important we include this information right in the email and make it as easy as possible.
We should also clean up some of the content as well, for example the title of the page is a little strange: "Activate all GitLab Enterprise Edition functionality with a license"