Sharing dirs and more

New

• A dockerfile for a test host container has been added. The purpose of this
  container is to serve as a general purpose test host, which includes by
  default several tools (iperf, tcpdump, for example) that are useful for test
  case execution.
• Fixing default host image in ubuntu:14.04. The default image for hosts
  used to be ubuntu:latest but since the actual image to which this points
  to can change, it could introduce issues for test cases that were developed
  under the assumption that the pointed-to image included the necessary tools
  for the test case.
• Logging the image and container data. Image name, id, creation date, etc. are
  now logged automatically for every container.
• Docker nodes now mount their /tmp directory under the host /tmp. The
  mount path of this directory under the host /tmp is defined using the
  container id.
• A new test that checks the proper functionality of host routes has been
  added. This is a functional test in which 2 hosts ping each other.

Changes

• Documentation for image attribute has been improved. This attribute was a
  source of confusion since it was not explicitly documented that the TAG
  column needed to be included in the image value.

Fixes

• Nodes which fail to start are now not considered for rollback. Also, this
  rollback process is now a best effort since it just tries to stop nodes. If
  one of these nodes fails to stop, this will be logged and the process will
  continue.