Talisker

-------------------

* Change requests.TaliskerAdapter to require scheme (435)
* Do not assume requests Connection error always wraps a urllib3.Retry error. (434)

-------------------

* Fix no content responses by still trying to call start_response() early (431)

-------------------

* Make raven an optional dependency (429)
* properly support super lazy WSGI apps, like werkzeug's debugger

-------------------

* Make gunicorn an optional dependency
* Fix use of werkzeug debugger

-------------------

This release includes a fair amount of internal refactoring, and some new features.

* Logs and metrics for timeouts in gunicorn (412)
* Errors are now handled in WSGI, and return text/html/json per Accept header (409)
* Soft timeouts are sent after the request is finished (411)
* Add requests.TaliskerAdapter, a requests transport adapter with loadbalancing and retries (experimental, 405, 408)
* Move logging from gunicorn into WSGI middleware (402)
* Don't use raven's WSGI middleware, do it in our middleware (406)
* All /_status/info/ endpoints support rendering JSON as well as text and HTML (407)
* support rendering json responses as well as text and html (407)
* move the request-id header name to config (401)
* fix requests latency buckets (413)

-------------------

* add additional sanitised keys by default, and add config for additional keys. Requires raven 6.4 (392)
* fix parsing of extra['start_time'] being a string in recent raven (390)