many lint fixes and optimizations (#17)

* util/kubernetes: drop stale files
* debug/log/kubernetes: drop stale files
* util/scope: remove stale files
* util/mdns: drop stale files
* lint fixes

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util/http/http.go

@@ -60,10 +60,9 @@ func NewRoundTripper(opts ...Option) http.RoundTripper {
 // RequestToContext puts the `Authorization` header bearer token into context
 // so calls to services will be authorized.
 func RequestToContext(r *http.Request) context.Context {
-	ctx := context.Background()
-	md := make(metadata.Metadata)
+	md := metadata.New(len(r.Header))
 	for k, v := range r.Header {
-		md[k] = strings.Join(v, ",")
+		md.Set(k, strings.Join(v, ","))
 	}
-	return metadata.NewContext(ctx, md)
+	return metadata.NewIncomingContext(r.Context(), md)
 }