Add StopWatch

Author: dbellettini

src/Clock.php

@@ -11,4 +11,6 @@ interface Clock extends ClockInterface
     public function asUTC(): UTCClock;
 
     public function asMicrotime(): MicrotimeClock;
+
+    public function stopWatch(): StopWatch;
 }

src/Clock/AbstractClock.php

@@ -6,6 +6,7 @@
 
 use Recruiter\Clock;
 use Recruiter\MicrotimeClock;
+use Recruiter\StopWatch;
 use Recruiter\UTCClock;
 
 abstract class AbstractClock implements Clock
@@ -19,4 +20,9 @@ public function asMicrotime(): MicrotimeClock
     {
         return new PsrMicrotimeClock($this);
     }
+
+    public function stopWatch(): StopWatch
+    {
+        return new StopWatch\ClockStopWatch($this);
+    }
 }