YAML Plugin add regex match group

[owochle]

Add a way to access match group of regex of from username inside to username to permit things like

- from:
    - username: "srv_(.*)"
      username_regex_match: true
  to:
    host: host-password:2222
    username: "$1"
    ignore_hostkey: true

then srv_root would redirect to user root on host-password, srv_user1 to user user1 etc...

[tg123]

good idea, will impl it or pr is welcomed for sure