Remove submodule and rely on Composer

PHP projects should depend on Composer for loading dependencies, not
submodules. Composer also provides a great autoloader.
Use a bash script in the bin

Switches the PHP script to be a bash/php script.
Fix namespaces on test suite

Fix the namespaces on the test suite, also fix the phpunit.xml file.
Reorg files to be PSR-0 compatible.
Update all examples to use the new autoloader