Now all test classes are namespaced, the old autoloader in the test bootstrap is no longer necessary.
Additionally, as long as Composer knows about the namespaced test classes. the (new) custom autoloader is only really needed when PHPUnit is run via a PHAR file.
To this end, this commit:
* Adds a
autoload-dev section to the
composer.json configuration file.
* Removes the old autoloader.
* And places the "manual" loading of the PHPUnit polyfills autoloader and the custom autoloader in a condition, so they only get used when the tests are run via a PHAR file.