This moves the responsibility for getting a valid class name
to the users of BridgeFactory, avoiding the repeated sanitation.
Improper use can also be checked statically.
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.
Jan Tojnar
Dag