__getattr__ should raise AttributeError, not EventsException

[DavidCurtiss]

When __getattr__ raises an EventsException for a missing attribute, it breaks getattr(obj, name, default).

Simple test that reproduces it:

class TestGetattr(TestBase):

    def test_getattr(self):
        events = Events(('on_event', ))
        assert getattr(events, "blah", None) is None

This is a problem for me because in python 3.8, creating a Mock of an object that has events runs into this issue. Here's the corresponding test case for python 3.8:

class TestMocking(TestBase):

    def test_mock(self):
        class MyEvents(Events):
            __events__ = ('on_eventOne', )
            _instance = None

        MyEvents._instance = MyEvents()

        # In python 3.8, this results in "EventsException: Event '_is_coroutine' is not declared"
        unittest.mock.Mock(MyEvents)