Check for datasheet URL HTTP status code

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It would be nice to have a script to check the HTTP status code returned for symbols' datasheet URLs. This could make HTTP HEAD requests for the URLs in the .dcm file, and give errors and warnings as appropriate for the different codes. It could even have an option to update URLs that return permanent redirects.

How should such a script be implemented? It doesn't seem inappropriate for the normal symbol checking scripts, except I don't think the framework for that is designed to handle potentially slow network I/O. Would a separate script be preferred, at least in the short term?