print usage when missing subcommand

[andrewdavidmackenzie]

Current situation

When you use a command and forget a required subcommand, say:

$ 3scale import

You get a "dry" response that doesn't help much.

import: no command given

So, you need to ask for help:

$ 3scale help import
NAME
    import - 3scale import command

USAGE
    3scale import <command> [options]

DESCRIPTION
    3scale import command.

SUBCOMMANDS
    csv     Import csv file

OPTIONS FOR 3SCALE
    -h --help          show help for this command
    -k --insecure      Proceed and operate even for server connections
                       otherwise considered insecure
    -v --version       Prints the version of this command

This helps a lot more and now I know that import requires a sub-command, such as csv

Proposed Change

When a command requires a subcommand and it is not supplied, print out the help for that command directly.

[andrewdavidmackenzie]

Note, this applies to the basic "no command" case also:

$ 3scale
3scale: no command given

Printout the usage/help no?