vendorize: update all vendorized packages. (#2206)

Bring in new changes from upstream for all the packages.

Important ones include
   - gorilla/mux
   - logrus
   - jwt

vendor/github.com/rs/xhandler/middleware.go

@@ -0,0 +1,59 @@
+package xhandler
+
+import (
+	"net/http"
+	"time"
+
+	"golang.org/x/net/context"
+)
+
+// CloseHandler returns a Handler, cancelling the context when the client
+// connection closes unexpectedly.
+func CloseHandler(next HandlerC) HandlerC {
+	return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
+		// Cancel the context if the client closes the connection
+		if wcn, ok := w.(http.CloseNotifier); ok {
+			var cancel context.CancelFunc
+			ctx, cancel = context.WithCancel(ctx)
+			defer cancel()
+
+			notify := wcn.CloseNotify()
+			go func() {
+				select {
+				case <-notify:
+					cancel()
+				case <-ctx.Done():
+				}
+			}()
+		}
+
+		next.ServeHTTPC(ctx, w, r)
+	})
+}
+
+// TimeoutHandler returns a Handler which adds a timeout to the context.
+//
+// Child handlers have the responsability of obeying the context deadline and to return
+// an appropriate error (or not) response in case of timeout.
+func TimeoutHandler(timeout time.Duration) func(next HandlerC) HandlerC {
+	return func(next HandlerC) HandlerC {
+		return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
+			ctx, _ = context.WithTimeout(ctx, timeout)
+			next.ServeHTTPC(ctx, w, r)
+		})
+	}
+}
+
+// If is a special handler that will skip insert the condNext handler only if a condition
+// applies at runtime.
+func If(cond func(ctx context.Context, w http.ResponseWriter, r *http.Request) bool, condNext func(next HandlerC) HandlerC) func(next HandlerC) HandlerC {
+	return func(next HandlerC) HandlerC {
+		return HandlerFuncC(func(ctx context.Context, w http.ResponseWriter, r *http.Request) {
+			if cond(ctx, w, r) {
+				condNext(next).ServeHTTPC(ctx, w, r)
+			} else {
+				next.ServeHTTPC(ctx, w, r)
+			}
+		})
+	}
+}