- 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.
- rename MuxHelper -> PathRecorderMux
- move non-rest handlers into routes packages within genericapiserver and
`pkg/routes` (those from master)
- move ui and logs handlers out of genericapiserver (they are
not generic)
- make version handler configurable (`config.EnableVersion`)
