title: HTML formatted Plot title text in Bokeh
body: <p>I would like to format a figure's title text to display a tooltip on hover using bootstrap in bokeh. I know that you can add Div widget (<a href="http://docs.bokeh.org/en/latest/docs/user_guide/interaction/widgets.html#div" rel="nofollow noreferrer">http://docs.bokeh.org/en/latest/docs/user_guide/interaction/widgets.html#div</a>) but I was wondering if there was an easy to format text, specifically the title, using html?</p>