Add my ssh key.

Add my ssh key to users.pp.  I will need ssh access to the Asterisk
server to be able to debug issues.

Change-Id: Idab037c996c3b0a833310551c3a71fe763db7ecd
Add a skeleton asterisk server.

This commit adds a bare server that will be updated to become an
Asterisk server.

Change-Id: If54badab3269d8c8ce504f8bfcb0e5f79eeaeb69
Install Asterisk

Add the necessary bits to get Asterisk installed on the pbx node.
This is using Asterisk 11 from Digium's repo.

Change-Id: I200789c7ee7fc1fb2e0779a38db2ea35ead998ae
Install Asterisk sounds

In addition to installing Asterisk itself, we want to install some sound
packages.  This includes a large set of prompts, as well as some music on
hold files.

Change-Id: I197079cb2398f97ae82abf38a18d5cb8c377b5bc
Allow specification of public UDP ports

The iptables class allowed specifying a list of public UDP ports,
just like it has support for TCP.  However, a couple of places needed
to be updated to pass through the UDP port list to make it usable.

Change-Id: I00764bf1d7baff862fa51a6cd03211fe9a29ecdd
Set up basic Asterisk configuration

This commit sets up the basic configuration for Asterisk.  It will allow
Asterisk to run, but it won't do anything useful yet.

Change-Id: I7975082ff5351db4dc6e3c8cf9dd2d90675e3108