Fix: Setting GUI is now modified such that sphinx configurations will only be controlled by SphinxEnable checkbox instead of by the availability of command line command "sphinx-build"
Fix: Now subprocess exceptions are rendered correctly. (Shown as red letters instead of black letters)
Add: Because of GUI changes, several unit tests are changed accordingly. One more test case (test_uiCheck8a) is added to test the effect of toggling sphinx enable/disable. Redundant unit test (test_uiCheck18) is deleted.
Todo:
1. Figure out why dock will disappear. Based on test_uiCheck17, try to build test_uiCheck17a with sphinx.
2. Check the correctness of user defined sphinx executable. Provide visual feedback by showing a message box.