Downloading malformed `plot-schema.json` can cause `import plotly` to break

[chriddyp]

See #612 for the original issue that prompted this discussion.

To make sure that this never happens again, we should either:

• Extend the try / except around the construction of graph_objs off of the downloaded plot-schema.json and use the cached version if it does not work
• Remove the auto-downloading plot-schema.json on import and perform more frequent (weekly) releases of the python library in sync with the plotly.js version updates.

[etpinard]

The more radical solution is implemented in #614

[rcscott]

I feel strongly that the auto-downloading should be removed. If someone wants the newest features then they can upgrade their plotly version. It's a strange design decision that the library can change automatically even if I have a specific version in my requirements.txt.

[theengineear]

Removed in 1.13.0.