Dashboard needs to be set up every time

[mrocklin]

I suspect that we need to update the JLab workspace yaml file. Everything looks fine when you first start up, but once you actually create a cluster things reset poorly. cc @ian-r-rose

[ian-r-rose]

I believe this is a result of drift between the individual plots names and the defaults in dask-labextension. When there is a mismatch, we currently bail.

This is fixable by getting #187 over the line and fixing dask/dask-labextension#216