Python Test Suite Revamp
 Moving towards a full Python Test Suite
We are pythonizing runtest, and refactoring Testing.py to provide:
- Test suite should run out of the box as is run nighty (no args needed for skip list, tests for optional plugins, etc)
- Data path formation that will work on Windows.
- Eventual support for running tests on Windows.
- Support for -d --data-dir (alternate data dir)
- Support for -o --output-dir (alternate output dir)
- Support to launch & log several test cases at once.
- Removal of old / unsupported diagnostics.
- Support for non visit cli tests
- Log of any python exceptions
- --retry option, which reruns the test suite only on failures from the previous test run run.
 Testing.py Changes
- name change to visit_test_main.py
- refactor to remove use of global vars
- better logging and report generation
- remove use of diff from command line, use python difflib