Log the command line flags

With d7ddcca231, we lost the logging
of the flags. We should at least log what the command line flags
were used to start processes as those incredibly useful for trouble shooting.

cmd/kube-proxy/app/BUILD

@@ -67,6 +67,7 @@ go_library(
         "//pkg/proxy/ipvs:go_default_library",
         "//pkg/proxy/userspace:go_default_library",
         "//pkg/util/configz:go_default_library",
+        "//pkg/util/flag:go_default_library",
         "//pkg/util/ipset:go_default_library",
         "//pkg/util/iptables:go_default_library",
         "//pkg/util/ipvs:go_default_library",

cmd/kube-proxy/app/server.go

@@ -63,6 +63,7 @@ import (
 	"k8s.io/kubernetes/pkg/proxy/ipvs"
 	"k8s.io/kubernetes/pkg/proxy/userspace"
 	"k8s.io/kubernetes/pkg/util/configz"
+	utilflag "k8s.io/kubernetes/pkg/util/flag"
 	utilipset "k8s.io/kubernetes/pkg/util/ipset"
 	utiliptables "k8s.io/kubernetes/pkg/util/iptables"
 	utilipvs "k8s.io/kubernetes/pkg/util/ipvs"
@@ -333,6 +334,8 @@ addon that provides cluster DNS for these cluster IPs. The user must create a se
 with the apiserver API to configure the proxy.`,
 		Run: func(cmd *cobra.Command, args []string) {
 			verflag.PrintAndExitIfRequested()
+			utilflag.PrintFlags(cmd.Flags())
+
 			cmdutil.CheckErr(opts.Complete())
 			cmdutil.CheckErr(opts.Validate(args))
 			cmdutil.CheckErr(opts.Run())