Allow PHP 5.2 autoloaders to consume namespace, classmap and include path files, fixes #1730
Travis using PHPUnit version from require-dev

in order not to use system version of PHPUnit and have unexpected bugs - it could be better to invoke PHPUnit from development dependencies

removing xdebug extension

modified travis executable
Merge pull request #1736 from nfx/patch-1

Travis using PHPUnit version from require-dev