XD-1545 Acc testing for multiple containers.  

1. Test no longer relies on artifact to know what containers are available.  This is queried from admin.
2. Test finds the container where source, processor, job & sink modules are deployed.
3. Mapped ec2 internal dns to external dns.
4. Tests handle x containers for source & job file based tests.
5. Sample properties container settings have been removed.
6. jclouds-ec2 dependency added to build.gradle.  It is compile time since it is utility based.
Thought down this track as well.  The problem with giving it to the postData, is that is a fixture that has no knowledge of how to find a container.  We could do something like sources.containerHttp("dataSender").postData(data).