Update release-notes.md
Update release-notes.md

add details on Windows Server 1803 support
thaJeztah/docker.github.io,anweiss/docker.github.io,docker/docker.github.io,anweiss/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,anweiss/docker.github.io,londoncalling/docker.github.io,londoncalling/docker.github.io,anweiss/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,anweiss/docker.github.io,docker/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io