move the SSH password login check out of setup because it interfers with Vagrant and into a separate script that we'll use for auditing in a later phase
Vagrant updates

* use a public box (the official Ubuntu 14.04 box which contra the description does have VBox Guest Additions installed)
* now that we allow SSH password logins, since Vagrant requires it, dont muck with sshd_config here
* don't put the machine on the public network because that will allow anyone to log into it with Vagrant's default username/password, duh
show less output when updating DNS configuration
allow dashes in emails during validation, and for aliases allow a much wider range of characters, fixes #64

* for local mail users, also disallows periods at the beginning or end of the local or domain parts
* Dovecot gets confused if the string contains any unusual characters, so local mail users are restricted to a narrow regex
* for mail aliases Postfix is not confused so use a regex based on RFC 2822