Although each of these command implementations has good output for
"west <command> --help", the "west --help" output is missing the
one-line descriptions.
Add them by modifying west-commands.yml to use a new 'help' key in
each command name. These need to be kept in sync with the Python
sources. For now just do that by copy/pasting. We could add fancy
logic to load the help from west-commands.yml later if we want.
Signed-off-by: Marti Bolivar <marti@foundries.io>
