Support using paramiko to set up accelerate connection

Adds original_transport attribute to Runner to track what the original
transport was before it is changed to 'accelerate'.
If using paramiko in original_transport, uses ParamikoConnection.  If
not, falls back to SSHConnection like before.
Merge branch 'issue4022' of https://github.com/sfromm/ansible into sfromm-issue4022

Conflicts:
	lib/ansible/runner/connection_plugins/accelerate.py