provision, deploy, testing: moving deploy interface to deploy dir

Also created an App interface in deploy pkg, so it won't need to import
provision.
provision/docker/provisioner: changing provision struct name

s/LocalProvisioner/DockerProvisioner
provision/juju,provision/lxc,provision: go fmt
provision/juju: sleeping 3 seconds to wait for terminate machine goroutine to end
provision/lxc/provisioner: s/LocalProvisioner/LXCProvisioner