fix(api): no retries on error

[mavolin]

Regarding: httputil.Client.Request

Currently, Request retries on any HTTP Response status that is < 200 or > 299.
However, many errors won't get resolved by a retry, as only 5xx errors indicate a server error and any other status indicates either an error with the data that was sent, etc..
An exception to this is of course code 429 - too many requests which indicates rate limiting.
See also https://en.wikipedia.org/wiki/List_of_HTTP_status_codes.

I would propose to check for server or rate limit errors and retry only then, but let all others break the loop and get handled respectively.
This could be done by simply replacing the

if status = r.GetStatus(); status < 200 || status > 299 {
    continue
}

with

if status = r.GetStatus(); status == http.StatusTooManyRequests || status >= 500 {
    continue
}

.

If you create a branch for it, I can hand in a PR for it.

[diamondburned]

You can PR straight into master, that's fine.

[mavolin]

Wow, that was quick! Will do.