Override check_origin from tornado.websocket
Fix test suite

 + Install VPCS and dynamips from GNS3 PPA
 + Drop netifaces-py3 from requirements.txt
 + Fix/update tests to use installed VPCS and dynamips
Modify the TRAVIS environment check
Update test_hypervisor.py

 + test_stdout: use system dynamips
 + test_stdout: correct host address to start dynamips on
Further test fixes

 + tests/dynamips/test_hypervisor.py: Increase sleep time to prevent
   random test failures
 + tests/iou/test_iou_device.py: Rework test skipping based on presence
   of IOU image rather than environment variable
Remove un-needed imports
Streamline TravisCI build

 + As we use Tox there's no need to run seperate builds for
   python3.3 and python3.4
 + There's no need to install the requirements in main
   environment as all dependencies are handled in the Tox
   virtualenv's
revert not installing requirements outside of tox
Further optimise the Travis testing and improve running tests for a user

  + Convert setup.py test to run py.test instead of tox
  + Tox should now run setup.py test
  + TravisCI will create a job for each TOX_ENV and then execute
    tox to run the tests for that TOX_ENV
Remove commented line, not needed anymore
Merge pull request #27 from dlintott/master

Override check_origin and fix test suite