bump phpunit & added dev namespace

composer.json

@@ -21,7 +21,7 @@
 		"php": ">=5.6.0"
 	},
 	"require-dev": {
-		"phpunit/phpunit": "5.2.*"
+		"phpunit/phpunit": "5.3.*"
 	},
 	"suggest": {
 		"chillerlan/php-googleauth": "*"
@@ -30,5 +30,10 @@
 		"psr-4": {
 			"chillerlan\\QRCode\\": "src/"
 		}
+	},
+	"autoload-dev": {
+		"psr-4": {
+			"chillerlan\\QRCodeTest\\": "tests/"
+		}
 	}
 }