Move serve_multiple, fix tests (#357)

* Move serve_multiple, remove stop_events, fix tests

Moves serve_multiple out of the app, removes stop_event (adds a
deprecation warning, but it also wasn't doing anything) fixes
multiprocessing tests so that they don't freeze pytest's runner.

Other notes:

Also moves around some imports so that they are better optimized as
well.

* Re-add in stop_event, maybe it wasn't so bad!

* Get rid of unused warnings import

tests/test_logging.py

@@ -1,4 +1,5 @@
 import asyncio
+import uuid
 from sanic.response import text
 from sanic import Sanic
 from io import StringIO
@@ -9,10 +10,11 @@ logging_format = '''module: %(module)s; \
 function: %(funcName)s(); \
 message: %(message)s'''
 
+
 def test_log():
     log_stream = StringIO()
     for handler in logging.root.handlers[:]:
-            logging.root.removeHandler(handler)
+        logging.root.removeHandler(handler)
     logging.basicConfig(
         format=logging_format,
         level=logging.DEBUG,
@@ -20,14 +22,16 @@ def test_log():
     )
     log = logging.getLogger()
     app = Sanic('test_logging')
+    rand_string = str(uuid.uuid4())
+
     @app.route('/')
     def handler(request):
-        log.info('hello world')
+        log.info(rand_string)
         return text('hello')
 
     request, response = sanic_endpoint_test(app)
-    log_text = log_stream.getvalue().strip().split('\n')[-3]
-    assert log_text == "module: test_logging; function: handler(); message: hello world"
+    log_text = log_stream.getvalue()
+    assert rand_string in log_text
 
-if __name__ =="__main__":
+if __name__ == "__main__":
     test_log()