Fix python version check in ParaViewWeb tests
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
We had attempted to avoid scheduling paraviewweb tests on machines where the Python version wasn't at least 2.7, but it was not working correctly, as machines with only Python 2.6 are still scheduling the tests. Then the tests are failing on those dashboards, as expected, because Python version isn't sufficient.