Fix: Code cleanup and TODO items marked out. Add exception handling for shutil copy function.
Fix: moving _copySphinxProjectTemplate from __init__.py to preview.py
Fix: Modified test workbench to wait on the correct signal: "loadFinished" from mainFrame instead of  "htmlReady" from converter thread.
Todo: Modularize code, make it compact.
Update: Update contents.rst to index.rst since CodeChat has updated to version 0.0.12a4
Fix: Preview should be disabled if an untitled document (tmp document, not saved, no filePath) is opened.
Fix: Modularize when to use sphinx.
Fix: embedded os.path.commonprefix has a bug. A new commonpath method has been designed to bypass the bug which might cause error if one sphinx project is '\a\b' while a codechat project is '\a\bb'
Update: Only save current document if sphinx will be used and BuildOnSave disabled.
Update: disable trailing whitespace stripping when autosaving. Mannual saving will always trigger trailing whitespace stripping.