Use relative paths for tarsnap archives
Move NameVirtualHost directives to ports.conf
Set two variable files from site.yml

That way we can override all the config from a central location. The
`user.yml` file overrides `defaults.yml`. `user.yml` was added to
`.gitignore` in order to allow a user to change it without having to
worry about merges. It's easy to do a diff to see what changed between
the defaults and your own settings.

Needs documentation, this is just a proposal.

Refs #39
Remove variables from roles

Refs #39
Comment defaults

That way the default values will not be applied by mistake. The user
needs to uncomment the lines from `vars/users.yml` and set them.

Also renamed openvpn variables.

Refs #39
Add explanations to the variable files

Refs #39
Add extra comment to sections

That way it's more convenient to uncomment an entire paragraph.
Merge pull request #50 from lukecyca/tarsnap-warning-fix

Tarsnap warns about leading /
Merge pull request #49 from lukecyca/apache-vhost-fix

Apache vhost misconfiguration
Merge pull request #47 from greenalto/global_config

Set two variable files from site.yml
new user vars file, move client usage info to wiki
hey this ain't Markdown
Tell the user to use Vagrant 1.3.x
README cleanups
Merge pull request #51 from greenalto/vagrantfile_comment

Tell the user to use Vagrant 1.3.x
Update Vagrantfile