Accessing getters on EntityIterator directly sometimes buggy

When accessing methods on the EntityIterator directly, one should always get the same results as if accessed directly on the first subelement of the Iterator. However, this was sometimes buggy - e.g. when properties were dynamically generated via certain methods. In such cases, methods should be tried first.

Offending code is `__call` and `__get` magic metods inside EntityIterator.
