Follow PSR-4

[felixfbecker]

http://www.php-fig.org/psr/psr-4/

The classes shouldn't be all in a single api.php file, but rather one class per file, with namespaces mapping to directories. Instead of explicit requires, Composer should handle autoloading.

[lord2800]

Is there going to be any movement on this issue any time soon? This is blocking our ability to use composer v2.