Merge Scheduler Bokeh Servers

Currently we have two Bokeh servers on the scheduler

1. A Bokeh server in a separate process, currently hosted at 8787
2. A Bokeh server in the same process as the scheduler, currently hosted at 8788

This is a bit confusing. Also the server in a separate process is hard to work on and extend. It would be nice to move everything into the in-process bokeh server.

However, the Bokeh servers aren't free. It would be good to verify that they're not taking up substantial resources from the actual work of scheduling. Additionally, we'll have to scrape up all of the current machinery required to produce the task stream plot and remove most of it. This will be satisfying but may require some effort, as code to produce the data, move it to the bokeh side, collect it, and then visualize it is all in different locations.