DCOS CLI help should show the list of commands

[arun-gupta]

Please answer the following questions before submitting your issue. Thanks!

What version of DC/OS + DC/OS CLI are you using (dcos --version)?

If DC/OS CLI version < 0.4.5, DC/OS version can be found at http://dcos_url/dcos-metada/dcos-version.json

dcoscli.version=0.4.17
dcos.version=1.9.2
dcos.commit=af6ddc2f5e95b1c1d9bd9fd3d3ef1891928136b9
dcos.bootstrap-id=79a0dfe0944948a33ab75f6e62335f166e117f3d

What operating system and version are you using?

OSX 10.12.5

What did you do?

If possible please provide a recipe for reproducing.

dcos --help shows the following message:

Description:
    The Mesosphere Datacenter Operating System (DC/OS) spans all of the machines in
your datacenter or cloud and treats them as a single, shared set of resources.

Usage:
    dcos [options] [<command>] [<args>...]

Options:
    --debug
        Enable debug mode.
    --help
        Print usage.
    --log-level=<log-level>
        Set the logging level. This setting does not affect the output sent to
        stdout. The severity levels are:
        The severity level:
        * debug    Prints all messages.
        * info     Prints informational, warning, error, and critical messages.
        * warning  Prints warning, error, and critical messages.
        * error    Prints error and critical messages.
        * critical Prints only critical messages to stderr.
    --version
        Print version information

Environment Variables:
    DCOS_CONFIG
        Set the path to the DC/OS configuration file. By default, this variable
        is set to ~/.dcos/dcos.toml.
    DCOS_DEBUG
        Indicates whether to print additional debug messages to stdout. By
        default this is set to false.
    DCOS_LOG_LEVEL
        Prints log messages to stderr at or above the level indicated. This is
        equivalent to the --log-level command-line option.

What did you expect to see?

It should include the list of commands as well.

What did you see instead?

[armandgrillet]

It does now:

➜  ~ dcos --version
dcoscli.version=632a2babfbc127748548a4890d92e872e8406841
dcosdcos.version=1.12.0
dcos.commit=0f988ed55edd2123a215cf048f398fae0f5eafbc
dcos.bootstrap-id=12159f5ab9401460b7ff1138d4d0f8cb9185fae1
➜  ~ dcos --help
Usage:
  dcos [command]

Commands:
  auth
      Authenticate to DC/OS cluster
  backup
      Access DC/OS backup functionality
  cluster
      Manage your DC/OS clusters
  config
      Manage the DC/OS configuration file
  help
      Help about any command
  job
      Deploy and manage jobs in DC/OS
  license
      Manage your DC/OS licenses
  marathon
      Deploy and manage applications to DC/OS
  node
      View DC/OS node information
  package
      Install and manage DC/OS software packages
  plugin
      Manage CLI plugins
  security
      DC/OS security related commands
  service
      Manage DC/OS services
  task
      Manage DC/OS tasks

Options:
  --version
      Print version information
  -v, -vv
      Output verbosity (verbose or very verbose)
  -h, --help
      Show usage help

Use "dcos [command] --help" for more information about a command.