A quick mockup for creating a step line.
Meir posted a question on the bokeh mailing list wondering how to do this: https://groups.google.com/a/continuum.io/forum/#!topic/bokeh/jmWFAtr20I0
I realized that such a plot might provide an interesting view for some work I was doing - so I provided a quick solution.
Below is the before/after of using the function:
Before:
After: