* add phpunit as a dev dependency

* add some basic tests for UrlHelper::rewrite_relative()
 * fix UrlHelper::rewrite_relative() to work better on non-absolute
   relative URL paths

vendor/phpunit/php-text-template/README.md

@@ -0,0 +1,12 @@
+# Text_Template
+
+## Installation
+
+You can add this library as a local, per-project dependency to your project using [Composer](https://getcomposer.org/):
+
+    composer require phpunit/php-text-template
+
+If you only need this library during development, for instance to run your project's test suite, then you should add it as a development-time dependency:
+
+    composer require --dev phpunit/php-text-template
+