This fixes a regression introduced in commit b1edcf34d0.
Also don't use any option after `-R` just to be safe. The zshbuiltins(1)
manual states:
> Only the -e and -n flags are recognized after -R; all other arguments
> and options are printed.
listing modules that are frozen or exernal.
Also be less colorful. And some other minor fixes: allow autoloading a
function name that starts with `-`, and add required quotes around
command subsitution (otherwise words are split).
Using the `list` action with `-v` shows all current details for the
existing modules.
Don't try to install or update external modules, since they have an
absolute path instead of a valid URL.