* VAULT-1303 when a request to vault fails, show namespace if set
* Adding changelog
* Fix Changelog file name
* Set namespace in ResponseWriter headers if it is set
* Using consts.NamespaceHeaderName instead of the literal string
* hghaf099-VAULT-1303-Adding namespace in error when it is set
* casting ResponseWriter in handleMonitor to logical.NamespaceResponseWriter
* Casting ResponseWriter conditionally for http.Flusher
Adding changelog
* Improving changlog message
* Return specialized error type
* Add a helper for extracting gRPC codes from errors
* Fix spacing in example
* Drop grpc codes
* Fix storing of decoded errors
* Allow returning list information and other data in 404s.
On read it'll output data and/or warnings on a 404 if they exist. On
list, the same behavior; the actual 'vault list' command doesn't change
behavior though in terms of output unless there are no actual keys (so
it doesn't just magically show other data).
This corrects some assumptions in response_util and wrapping.go; it also
corrects a few places in the latter where it could leak a (useless)
token in some error cases.
* Use same 404 logic in delete/put too
* Add the same secret parsing logic to the KV request functions
