Suggestion to add repmgr version to repmgr node status command output

[xinferum]

Good afternoon.

Currently, the output of the repmgr node status command (https://repmgr.org/docs/current/repmgr-node-status.html) does not contain information about the version of repmgr installed on this node.

It would be convenient to see the repmgr version in the output, for example:

$ repmgr -f /etc/repmgr.conf node status
Node "node1":
    PostgreSQL version: 10beta1
    Repmgr version: 5.3.2
    Total data size: 30 MB
    Conninfo: host=node1 dbname=repmgr user=repmgr connect_timeout=2
    Role: primary
    WAL archiving: off
    Archive command: (none)
    Replication connections: 2 (of maximal 10)
    Replication slots: 0 (of maximal 10)
    Replication lag: n/a