THRIFT-1743: Add composer.json for new Symfony 2.1 Dependency Manager

From 583c1107169ed4ea8880e7e660064797c4759b7a Mon Sep 17 00:00:00 2001
From: Mauro Maggi <mauro.maggi@immobiliare.it>
Date: Fri, 28 Mar 2014 12:27:05 +0100
Subject: [PATCH 1/3] Add Composer.json for Thrift 0.9.1 release

Github Pull Request: This closes #90