Package builder

[dwilkie]

This PR contains infrastructure for building debian debs for FreeSWITCH

We have the following options for running FreeSWITCH in docker.

1. Use Signalwire debian packages

Cons:

• Need to use Signalwire key to build docker
• Can't use source code for latest bug fixes
• No arm64 support (t4 instances)

2. Compile from source

Cons:

• Need to use Signalwire key to get build dependencies for FreeSWITCH
• Non-standard installation location

3. Compile own debian packages from source.

Pros:

• No need to use Signalwire key
• We control the packages
• Can use script to minimize docker image
• arm64 support

Cons:

• Need to setup Debian CI Server on AWS