Better initial help message

Currently cookietemple --help gives an overview of every command.

I quite like the gh help message, which looks like this:

zeth@master ~> gh --help                                                                                                                                                               (base) 
Work seamlessly with GitHub from the command line.

USAGE
  gh <command> <subcommand> [flags]

CORE COMMANDS
  issue:      Create and view issues
  pr:         Create, view, and checkout pull requests
  repo:       Create, clone, fork, and view repositories

ADDITIONAL COMMANDS
  alias:      Create shortcuts for gh commands
  api:        Make an authenticated GitHub API request
  completion: Generate shell completion scripts
  config:     Manage configuration for gh
  gist:       Create gists
  help:       Help about any command

FLAGS
      --help              Show help for command
  -R, --repo OWNER/REPO   Select another repository using the OWNER/REPO format
      --version           Show gh version

EXAMPLES
  $ gh issue create
  $ gh repo clone cli/cli
  $ gh pr checkout 321

LEARN MORE
  Use "gh <command> <subcommand> --help" for more information about a command.
  Read the manual at http://cli.github.com/manual

FEEDBACK
  Fill out our feedback form https://forms.gle/umxd3h31c7aMQFKG7
  Open an issue using “gh issue create -R cli/cli”

I quite like the Examples, Learn More and Feedback sections.

What do you think @filipdutescu @Imipenem ?

[Zethson]

Don’t think that we can create fat messages right @Imipenem ? They’re autogenerated from the docstrings…

Hence, I quite like the full caps “headers” actually @filipdutescu

[Imipenem]

I guess we have to write our custom thing here and then we can start styling it

Thats the way we should go for yes @Zethson