Extension of fetch which supports passing a
retry value in to
retry should be an integer,
n, and a fetch will be retried
n times (i.e.
n + 1 fetches in total) before failing.
allowedStatusCodes value in
options. This is an array of integers of status codes that if responded with, won't attempt to retry.
Fetches also have a
stopRetrying() method which will fulfil the promise with the reult of the current in-flight fetch and not send any more requests