PLT-4357 adding performance monitoring (#4622)

* WIP

* WIP

* Adding metrics collection

* updating vendor packages

* Adding metrics to config

* Adding admin console page for perf monitoring

* Updating glide

* switching to tylerb/graceful

vendor/github.com/prometheus/procfs/Makefile

@@ -0,0 +1,6 @@
+ci:
+	! gofmt -l *.go | read nothing
+	go vet
+	go test -v ./...
+	go get github.com/golang/lint/golint
+	golint *.go