Qscintilla Docs Save

Documentation for QScintilla editing component of the PyQt framework.
If there are mistakes, please open an issue on it.
If there is functionality that is not documented, open an issue and if I know anything about it, I will gladly add it.

Kristof Mulier also adapted the documentation into a great website at https://qscintilla.com/ .
It is prefered you use Kristof's website, as it is much easier to navigate and honestly better.