Support acloud delete command on the remote host.

BUG:146145520
Test: acloud-dev delete --host 1.1.1.1
      acloud-dev delete --host 1.1.1.1 --host-user [test] \
      --host-ssh-private-key-path [path]

Change-Id: I82bd3d68b0e4da0c05f42419bdc5e84f39d12a3a
3 files changed