Update upgrade.md
Update upgrade.md

Fixed https://github.com/docker/docs-private/pull/836/files#r230223172, https://github.com/docker/docs-private/pull/836/files#r230223631, https://github.com/docker/docs-private/pull/836/files#r230225394, and https://github.com/docker/docs-private/pull/836/files#r230236731
londoncalling/docker.github.io,thaJeztah/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io,docker/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io