Merge pull request #42 from wilmoore/feature/phpunit-version-note

Added note to README regarding phpunit 3.5+ being necessary

README.mdown

@@ -71,7 +71,8 @@ About
 Requirements
 ------------
 
-Any flavor of PHP 5.3 should do
+- Any flavor of PHP 5.3 should do
+- [optional] PHPUnit 3.5+ to execute the test suite (phpunit --version)
 
 Submitting bugs and feature requests
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