Revert phpunit to 3.7.* because 4.* is too slow sebastianbergmann/phpunit#1300

Author: ivanlanin

composer.json

@@ -36,7 +36,7 @@
         "ext-xml": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.*",
+        "phpunit/phpunit": "3.7.*",
         "phpdocumentor/phpdocumentor":"2.*",
         "squizlabs/php_codesniffer": "1.*",
         "phpmd/phpmd": "2.*",