Errors and Logging

[tylerflex]

• [ ] In web.download, if task.status != 'success', download the full log and load into SimulationData.log_string with no monitor_data.

[tylerflex]

@momchil-flex should we be raising td.AuthenticationError here? https://github.com/flexcompute/tidy3d/blob/develop/tidy3d/web/auth.py#L62

[tylerflex]

@momchil-flex where are we at with the first bullet point? If the simulation errors / diverges, what gets returned when we try to download? Or is this something we should just handle client-side, ie

try:
    # download simulation data
except:
    # download the json file
    # generate and return an empty simulation data.

[tylerflex]

consolidating in #544