Fix Qt CodeEditor pygments monkeypatch conflict with ipython.

Both the Qt CodeEditor and IPython monkeypatch the pygments'
RegexLexer.get_tokens_unprocessed in a slightly different manner,
which meant only the one imported later would work correctly.
This is fixed by now using same monkeypatch as ipython.
Merge pull request #100 from pankajp/qt_code_editor_pygments_monkeypatch_ipython_conflict

Fix Qt CodeEditor pygments monkeypatch conflict with ipython.