version number of CLI tools

[oberstet]

We should have a way to check the version number of the txaioetcd library and CLI tools, because:

ubuntu@ip-10-0-0-27:~$ /opt/txaioetcd/bin/etcd-export --version
usage: etcd-export [-h] [-a ADDRESS] [-k {utf8,binary}]
                   [-v {json,binary,utf8}] [-f {json,csv}] [-o OUTPUT_FILE]
etcd-export: error: unrecognized arguments: --version
ubuntu@ip-10-0-0-27:~$ /opt/txaioetcd/bin/etcd-export --help
usage: etcd-export [-h] [-a ADDRESS] [-k {utf8,binary}]
                   [-v {json,binary,utf8}] [-f {json,csv}] [-o OUTPUT_FILE]

Utility to dump etcd database to a file.

optional arguments:
  -h, --help            show this help message and exit
  -a ADDRESS, --address ADDRESS
                        Address(with port number) of the etcd daemon (default:
                        http://localhost:2379)
  -k {utf8,binary}, --key-type {utf8,binary}
                        The key type in the etcd database (default: utf8).
  -v {json,binary,utf8}, --value-type {json,binary,utf8}
                        The value type in the etcd database (default: json).
  -f {json,csv}, --output-format {json,csv}
                        The output format for the database dump (default:
                        json).
  -o OUTPUT_FILE, --output-file OUTPUT_FILE
                        Path for the output file. When unset, output goes to
                        stdout.

leaves me puzzled ..

[om26er]

First attempt: https://github.com/crossbario/txaio-etcd/pull/17