Cluster Model update

[ian-r-rose]

There is currently some churn going on in the interfaces for a generic distributed cluster info dict (cf. #78, #77 #73).

At the same time, this extension takes that information, and converts it to a ClusterModel dictionary, a JSON-serializable representation of the cluster information to display on the front end. This conversion happens here: https://github.com/dask/dask-labextension/blob/b68342bcfb43f905d7b86588fb3083f917519b5a/dask_labextension/manager.py#L240-L290

And it produces a dictionary with the typescript interface here: https://github.com/dask/dask-labextension/blob/b68342bcfb43f905d7b86588fb3083f917519b5a/src/clusters.tsx#L776-L820

Once the churn on the upstream side dies down, we should update the IClusterModel interface to be as close as possible to the generic cluster info dictionary, to which should help cut down on further confusion and maintenance.

n.b. This would be a breaking change, as both the client-side and the server-side would have to be updated with the new interface.

[mrocklin]

I'm not sure that that churn is affecting the structure of this dictionary though.

[ian-r-rose]

Which dictionary do you mean? I'm mostly referring to making IClusterModel look more like cluster.scheduler_info, so that we have to do fewer if/else/try/except checks, and more direct copying of the data.