Communicating API errors

[marcustyphoon]

#1271 is most likely an apifetch failure. We have a couple of problems:

• apiFetch failing does not always call notify with e.g. the friendly contents of body.errors[0].detail ("Looks like something went wrong. Please try again."). This has been implemented with try-catch in some places, but not universally.
• Wrapping async calls in try-catch is kind of clunky (got to either declare the result variable with let outside the try-catch or potentially catch something that doesn't have a body property from the code that uses the result).
• If one does implement that try-catch or .catch, the detailed contents of the error (for example, "APIError [404.8007] at https://www.tumblr.com/api/v2/blog/t:JxCENGvJBCX1BgkcOh_RDQ/posts/727925499598355500?fields[blogs]=name,avatar ()") are swallowed and do not show up in the javascript console.

Some thoughts I had about this were that the notify call, a console.error, or both could be in apiFetch itself (which could then re-throw). Maybe the notify call is better off as situational, though, as if the Tumblr API changes/breaks, that could result in a whole bunch of notifications with no context.