Update to pure-ftpd version 1.0.49

[Rid]

I understand that we're currently limited to the latest version provided in debian stretch.

Would it be worth me submitting a PR to build from the latest source upstream from https://github.com/jedisct1/pure-ftpd/releases ?

If not I'm happy to fork for my needs.

Thanks for the great work!

[stilliard]

Hi @Rid
Sorry for not getting back to you sooner.

I think I'd be interested in a new version, currently we're just using the apt repo to get the source, but switching that out to get it directly makes sense to me.

Submit a PR if you'd like & I'll review it :)