Migrate core from threads to async awesomeness (#3248)

* Add event loop to the core

* Add block_till_done to HA core object

* Fix some tests

* Linting core

* Fix statemachine tests

* Core test fixes

* fix block_till_done to wait for loop and queue to empty

* fix test_core for passing, and correct start/stop/block_till_done

* Fix remote tests

* Fix tests: block_till_done

* Fix linting

* Fix more tests

* Fix final linting

* Fix remote test

* remove unnecessary import

* reduce sleep to avoid slowing down the tests excessively

* fix remaining tests to wait for non-threadsafe operations

* Add async_ doc strings for event loop / coroutine info

* Fix command line test to block for the right timeout

* Fix py3.4.2 loop var access

* Fix SERVICE_CALL_LIMIT being in effect for other tests

* Fix lint errors

* Fix lint error with proper placement

* Fix slave start to not start a timer

* Add asyncio compatible listeners.

* Increase min Python version to 3.4.2

* Move async backports to util

* Add backported async tests

* Fix linting

* Simplify Python version check

* Fix lint

* Remove unneeded try/except and queue listener appproriately.

* Fix tuple vs. list unorderable error on version compare.

* Fix version tests

tests/components/test_mqtt_eventstream.py

@@ -50,7 +50,7 @@ class TestMqttEventStream(unittest.TestCase):
         self.assertEqual(self.hass.bus.listeners.get('*'), None)
 
         self.assertTrue(self.add_eventstream(pub_topic='bar'))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         # Verify that the event handler has been added as a listener
         self.assertEqual(self.hass.bus.listeners.get('*'), 1)
@@ -60,7 +60,7 @@ class TestMqttEventStream(unittest.TestCase):
         """"Test the subscription."""
         sub_topic = 'foo'
         self.assertTrue(self.add_eventstream(sub_topic=sub_topic))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         # Verify that the this entity was subscribed to the topic
         mock_sub.assert_called_with(self.hass, sub_topic, ANY)
@@ -76,7 +76,7 @@ class TestMqttEventStream(unittest.TestCase):
 
         # Add the eventstream component for publishing events
         self.assertTrue(self.add_eventstream(pub_topic=pub_topic))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         # Reset the mock because it will have already gotten calls for the
         # mqtt_eventstream state change on initialization, etc.
@@ -84,7 +84,7 @@ class TestMqttEventStream(unittest.TestCase):
 
         # Set a state of an entity
         mock_state_change_event(self.hass, State(e_id, 'on'))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         # The order of the JSON is indeterminate,
         # so first just check that publish was called
@@ -112,7 +112,7 @@ class TestMqttEventStream(unittest.TestCase):
     def test_time_event_does_not_send_message(self, mock_pub):
         """"Test the sending of a new message if time event."""
         self.assertTrue(self.add_eventstream(pub_topic='bar'))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         # Reset the mock because it will have already gotten calls for the
         # mqtt_eventstream state change on initialization, etc.
@@ -125,17 +125,17 @@ class TestMqttEventStream(unittest.TestCase):
         """"Test the receiving of the remotely fired event."""
         sub_topic = 'foo'
         self.assertTrue(self.add_eventstream(sub_topic=sub_topic))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         calls = []
         self.hass.bus.listen_once('test_event', lambda _: calls.append(1))
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         payload = json.dumps(
             {'event_type': 'test_event', 'event_data': {}},
             cls=JSONEncoder
         )
         fire_mqtt_message(self.hass, sub_topic, payload)
-        self.hass.pool.block_till_done()
+        self.hass.block_till_done()
 
         self.assertEqual(1, len(calls))