Added test configuration

Author: kore

phpunit.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit backupGlobals="false"
+         strict="true"
+         backupStaticAttributes="false"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         processIsolation="false"
+         stopOnFailure="false"
+         bootstrap="vendor/autoload.php"
+         syntaxCheck="false">
+
+    <testsuites>
+        <testsuite name="Unit Tests">
+            <directory>tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+      <whitelist>
+          <directory suffix=".php">src/</directory>
+      </whitelist>
+  </filter>
+</phpunit>