* Correctly displays inline code blocks with syntax highlighting turned on
as well as markdown at the same time
* Adds a context menu item for toggling markdown on and off which also
which essentially turns on/off all text processing
* Uses QTextDocument::MarkdownNoHTML to handle markdown in QTextDocument
which allows display of html tags like normal, but unfortunately does not
allow display of markdown tables as markdown
Signed-off-by: Adam Treat <treat.adam@gmail.com>