Set disabled even if no disabled option

to override the previous settings
Revise the unit case, too
core: only set ID on machine if data dir [GH-3827]
Update CHANGELOG
core: WaitForCommunicator always asks for state

This forces global-status to be up-to-date typically
synced_folders/rsync: rsync__chown [GH-3810]
core: cygwin_path only uses cygpath in cygwin [GH-3804]
providers/docker: don't use graceful shutdown [GH-3798]
Merge pull request #3783 from YungSang/topic

kernel/v2: set disabled to false whenever synced folder override
Update CHANGELOG
guests/darwin: respect NFS mount options [GH-3791]
providers/docker: retry container ssh command [GH-3763]
Add NixOS guest support
Merge pull request #3830 from cstrahan/nixos-guest

Add NixOS guest support
Update CHANGELOG