Server manager cli uses underscore for arguments instead of dash/hyphen

[Vedamurthy Joshi]

Typically in clis , there is a convention to use hyphen to separate words in arguments.
(ex: neutron/nova or any openstack related clis), They never use underscore.

But in server, its almost the opposite. It always uses underscore. This is pretty annoying to a user who is trained to use hyphens.

Ex:
bash-4.2$ /cs-shared/server-manager/client/server-manager reimage -h
usage: server-manager reimage [-h] [--config_file CONFIG_FILE]
                              [--package_image_id PACKAGE_IMAGE_ID]
                              [--no_reboot]
                              (--server_id SERVER_ID | --cluster_id CLUSTER_ID | --tag TAG)
                              [--no_confirm]
                              base_image_id

Reimage given server(s) with provided base ISO and package. Servers can be
specified by providing match condition to pick servers from the database.

positional arguments:
  base_image_id image id for base image to be used

optional arguments:
  -h, --help show this help message and exit
  --config_file CONFIG_FILE, -c CONFIG_FILE
                        Server manager client config file (default - /cs-
                        shared/server-manager/client/sm-client-config.ini)
  --package_image_id PACKAGE_IMAGE_ID, -p PACKAGE_IMAGE_ID
                        Optional contrail package to be used on reimaged
                        server
  --no_reboot, -n optional parameter to indicate that server should NOT
                        be rebooted following the reimage setup.
  --server_id SERVER_ID
                        server id for the server to be reimaged
  --cluster_id CLUSTER_ID
                        cluster id for the server(s) to be reimaged
  --tag TAG tag values for the servers to be reimagedin
                        t1=v1,t2=v2,... format
  --no_confirm, -F flag to bypass confirmation message, default = do not
                        bypass
bash-4.2$