support rsync from remote to local

[MacHu-GWU]

fix #26

The method is simple. Just add an argument remote_to_local to transfers.rsync function.

If the flag is True, then switch the source and target in the command template. And use keyword arguments instead of positioning argument style.

Solution:

    if host.count(":") > 1:
        # Square brackets are mandatory for IPv6 rsync address,
        # even if port number is not specified
        if remote_to_local:
            cmd = "rsync {options} [{user}@{host}]:{target} {source}"
        else:
            cmd = "rsync {options} {source} [{user}@{host}]:{target}"
    else:
        if remote_to_local:
            cmd = "rsync {options} {user}@{host}:{target} {source}"
        else:
            cmd = "rsync {options} {source} {user}@{host}:{target}"
    cmd = cmd.format(options=options, source=source, user=user, host=host, target=target)
    return c.local(cmd)

[MacHu-GWU]

@bitprophet Hi, I like your fabric project. I made a little improvement to make patchwork can rsync from remote to local. Please review. Thank you

[bpluly]

In implementing this for my own use I combined it with the work on integrating with Fabric => 3.0.0 using #46 (comment)