[Enhancement] Provide More Actionable Error Messages

Based on https://github.com/hydrosquall/tiingo-python/issues/157, it appears that when API calls return non-200 status codes, that the response may not necessarily be JSON parse-able.

We should find out whether there is a more specific error message coming from the API that can be provided to the user, and print those out accordingly.

See Taylor Barnett's "Guide to Technical Writing" for more tips on making error messages with the 3 H's in mind: humble, helpful, and human.

https://blog.stoplight.io/writing-documentation-when-you-arent-a-technical-writer-part-two-59997587cc2a?gi=67155dd06a2c