Add phpunit config

Author: clue

phpunit.xml.dist

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit colors="true">
+    <testsuites>
+        <testsuite name="Datagram Test Suite">
+            <directory>./tests/</directory>
+        </testsuite>
+    </testsuites>
+    <filter>
+        <whitelist>
+            <directory>./Datagram</directory>
+        </whitelist>
+    </filter>
+</phpunit>