Locator: join thread when terminating

Fix #236
workspace: set focus on newly opened document
tests: waitUntilPassed
tests: force main window to be active
tests: better behaviour if focus widget is not set
Fix: Delete 'htmlBuilding' signal
Fix: UI change. Log window is now plainTextEdit. It's still read-only.
Add: unicode test case
Fix: Now log window supports restructuredText
Add: Unit test for rsT support (merged with old unit test code)
Add: Log parser. Can tell which line and what is error type(ERROR/WARNING)
Add: Progressbar color indicates error(red)/warning(yellow)
Fix: Delete status label. With color coded progressbar, status label is not necessary
Fix: Regex and stylesheet update is not done instant, thus setting progress bar to default color before parsing log will cause a ~0.5 second green progressbar. If input text do have errors, this is misleading.

Add: 3 more tests for progressbar color. (These tests have to be done separately. Combining them into one test will somehow not show the correct result. I have tried reload GUI and resetting codechat option but still not work)

Add: One unit test for log parser. (Need more log parser unit tests)
Add: one more test case to test log window and progressbar behavior when switching between documents
Add: comments for log parser, especially the regex.
Fix: Simplify reST log parser.
     Improve log parser docs.
Docs: Clarify test case comments.
Add: Hack in HTML builder preview.
Add: Kludge in sphinx build.
Fix: Correct the save/restore scroll bar position.
Fix: Tidy up htmlReady processing.
     Tidy up _getHtml for an HTML builder.
Docs: Tidy.
Fix: Correctly handle None for _filePath in Sphinx generation check.
Docs: Updates.