added unit tests config

phpunit.xml.dist

+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit
+        backupGlobals="false"
+        backupStaticAttributes="false"
+        colors="true"
+        convertErrorsToExceptions="true"
+        convertNoticesToExceptions="true"
+        convertWarningsToExceptions="true"
+        processIsolation="false"
+        stopOnFailure="false"
+        syntaxCheck="false"
+        bootstrap="vendor/autoload.php">
+
+    <testsuites>
+        <testsuite name="All">
+            <directory>./tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory>./</directory>
+            <exclude>
+                <directory>./tests</directory>
+                <directory>./vendor</directory>
+            </exclude>
+        </whitelist>
+    </filter>
+
+    <logging>
+        <log type="coverage-text" target="php://stdout" showOnlySummary="true"/>
+    </logging>
+
+</phpunit>