Here's an initial go at getting some bash-completion for the tito
command-line. Module options are a union of those culled from both
"tito MODULE --help" and "man tito" -- there are discrepancies. Some
options were deliberately omitted such as those documented as deprecated
or "avoid using this please". All short options are also omitted as
their completion would not save any typing but would hinder the
accessibility of the longer options.