Add amqp-cpp

Summary:
Add tunnelbroker's amqp-cpp dependency.

This isn't currently available in nixpkgs, so we need to package it locally.

Depends on D3784

Test Plan: nix build .#amqp-cpp

Reviewers: varun, geekbrother, jimpo

Reviewed By: varun, geekbrother

Subscribers: jimpo, varun, ashoat, palys-swm, Adrian, atul, karol-bisztyga, benschac, yayabosh

Differential Revision: https://phabricator.ashoat.com/D3793