Added whitelist to phpunit.

Author: Martin Brecht-Precht

phpunit.xml.dist

@@ -5,4 +5,13 @@
 			<directory>test</directory>
 		</testsuite>
 	</testsuites>
+	<filter>
+		<whitelist>
+			<directory suffix=".php">./src</directory>
+			<exclude>
+				<directory>./vendor</directory>
+				<directory>./test</directory>
+			</exclude>
+		</whitelist>
+	</filter>
 </phpunit>