We cannot yet switch to namespaces for RSS-Bridge itself but for tests we are not limited by BC.
It does not actually do anything since PHPUnit will search for the test files without the help of the autoloader but it still makes the directory cleaner.
The format factory can be based on the abstract factory class if it
wasn't static. This allows for higher abstraction and makes future
extensions possible. Also, not all parts of RSS-Bridge need to work
on the same instance of the factory.
References #1001
