mod_client_management: Include client software version number in listing Should you ever wish to revoke a client by version number, e.g. for security reasons affecting certain versions, then it would be good to at the very least see which version is used. Also includes the OAuth2 software ID, an optional unique identifier that should be the same for all installations of a particular software.

Generate a DNS UPDATE order in format suitable for `nsupdate` based on
current port configuration.

Example output:

```
$ prosodyctl mod_dnsupdate -d example.com -t xmpp.example.com example.com
zone example.com
server ns1.example.com
ttl 3600
add _xmpp-client._tcp.example.com IN SRV 1 1 5222
add _xmpp-server._tcp.example.com IN SRV 1 1 5269
```