[PATCH] completion: fail silently if _init_completion is not found

[David Bremner]

Jani Nikula <jani at nikula.org> writes:

> The completion script depends on bash-completion 1.90 or later, with
> _init_completion function. If that's not present, for some reason, the
> completion currently fails with an ugly message, messing up user's
> command line:
>
> $ notmuch -bash: _init_completion: command not found
>
> It's better to just not complete

pushed.

d