This makes the behavior of the docker and hyperv provider consistent with the
virtualbox provider by raising an error on ssh actions if the machine is not
created or not running.
Fixes#8508
This adds a new core command, `docker-exec`, which allows the user to
exec into an already-running container.
- Fixes#6566
- Fixes#5193
- Fixes#4904
- Fixes#4057
- Fixes#4179
- Fixes#4903
Initial work
commands/up: make sure all names to with_target_vms are strings
providers/docker: create a docker host VM if needed
providers/docker: executor abstraction for driver to eventually support remote
providers/docker: vagrant executor
providers/docker: support creating the machine
providers/docker: status works if host VM is gone
providers/docker: use start fence to get real docker output
core: Call preserves stack ordering
core: support Message post option
providers/docker: Guard some features with HasSSH checks
providers/docker: much better messaging around create/destroy
providers/docker: output the container ID on create
providers/docker: copy the hostmachine Vagrantfile to the data dir
providers/docker: should make host machine before any up action
providers/docker: HandleBox before the host machine
providers/virtualbox: functional_vboxsf to disable vboxsf
providers/virtualbox: synced folder usable method should take 2 args
providers/docker: default machine name to :default