Fix asyncio.get_running_loop() monkey-patching (python-trio#83)

Author: niklasf

newsfragments/99.bugfix.rst

@@ -0,0 +1,2 @@
+:func:`asyncio.get_running_loop()` will now return the trio-asyncio event loop
+(if running), instead of failing with :exc:`RuntimeError`.

trio_asyncio/_loop.py

@@ -251,6 +251,8 @@ def _new_run_get_or_throw():
 
     _aio_event._get_running_loop = _new_run_get
     _aio_event.get_running_loop = _new_run_get_or_throw
+    asyncio._get_running_loop = _new_run_get
+    asyncio.get_running_loop = _new_run_get_or_throw
 
 #####