Add benchmarking code (#448)

* adding benchmarking code

* enable writing to file

* fix build

* time more stuff

* adding benchmarking to integration tests

* compare docker and kaniko times in integration tests

* Switch to setting benchmark file with an env var

* close file at the right time

* fix integration test with environment variables

* fix integration tests

* Adding benchmarking documentation to DEVELOPEMENT.md

* human readable benchmarking steps

pkg/timing/timing.go

@@ -18,7 +18,6 @@ package timing
 
 import (
 	"bytes"
-	"fmt"
 	"sync"
 	"text/template"
 	"time"
@@ -42,7 +41,6 @@ func (tr *TimedRun) Stop(t *Timer) {
 	if _, ok := tr.categories[t.category]; !ok {
 		tr.categories[t.category] = 0
 	}
-	fmt.Println(stop)
 	tr.cl.Lock()
 	defer tr.cl.Unlock()
 	tr.categories[t.category] += stop.Sub(t.startTime)