Adding in some security bits

Using the ufw recipe from opscode. Manually verified that this
is doing the stuff we want, and provides the firewall_rule resource
we want, but is doing so in a hard-to-test way. Removed the extra
tests in the firewall_spec because of this.

Started filling out the ssh server recipe. There's also an opscode
cookbook for this, but it is more complicated than desired here, so
just doing a simple method with a locked_down config instead
Starting to lock down ssh config
I went insane and ignored templates