Launch issues on 16.04

[nim65s]

Hi,

Following #15, trying to launch the first test on 16.04 yields the following error:

[Testcase: testtest_sot_talos_kine] ... ok

[ROSTEST]-----------------------------------------------------------------------

[talos_integration_tests.rosunit-test_sot_talos_kine/runTest][ERROR]------------
not all arguments converted during string formatting
  File "/usr/lib/python2.7/unittest/case.py", line 329, in run
    testMethod()
  File "/ws/install/lib/talos_integration_tests/start_talos_gazebo_kine.py", line 65, in runTest
    launch_gazebo_alone.start()
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/parent.py", line 268, in start
    self._start_infrastructure()
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/parent.py", line 217, in _start_infrastructure
    self._load_config()
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/parent.py", line 132, in _load_config
    roslaunch_strs=self.roslaunch_strs, verbose=self.verbose)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/config.py", line 450, in load_config_default
    logger.info('loading config file %s'%f)
--------------------------------------------------------------------------------


SUMMARY
 * RESULT: FAIL
 * TESTS: 1
 * ERRORS: 1
 * FAILURES: 0