Strip everything before slash in image name

spec/Dock/Docker/Dns/DnsDockResolverSpec.php

@@ -30,6 +30,6 @@ function it_removes_the_tag_in_image_name()
 
     function it_removes_the_slash_in_image_name()
     {
-        $this->getDnsByContainerNameAndImage('container', 'someone/image:latest')->shouldContain('container.someone_image.docker');
+        $this->getDnsByContainerNameAndImage('container', 'someone/image:latest')->shouldContain('container.image.docker');
     }
 }

src/Docker/Dns/DnsDockResolver.php

@@ -34,6 +34,10 @@ private function stripTagNameFromImageName($imageName)
 
     private function stripSlashFromImageName($imageName)
     {
-        return str_replace('/', '_', $imageName);
+        if (false !== ($position = strpos($imageName, '/'))) {
+            $imageName = substr($imageName, $position+1 );
+        }
+
+        return $imageName;
     }
 }