- move rest handler into handlers package
- move errors into handlers/errors package
- move negotation code into handlers/negotation package
- move http response writer helpers into handlers/responsewriter package
- split up pkg/apiserver/apiserver.go
Note: this is only an intermediate step towards a proper genericapiserver
package hierarchy.
Our typical HTTP Response has a "Date" Header, if we don't add an
additional http header "Access-Control-Expose-Headers: Date" then
the browser based clients cannot use the Date HTTP Header.
Fixes#33231
