update from Atlas with major reorg

attic/futures/future_yield2.py

@@ -0,0 +1,19 @@
+@asyncio.coroutine
+def a(future):
+    print('a, future:', future, hex(id(future)))
+    res = yield from future
+    return res
+
+def b():
+    future = asyncio.Future()
+    coro = a(future)
+    prime_result = next(coro)
+    print('b, prime_result:', prime_result, hex(id(future)))
+
+loop = asyncio.get_event_loop()
+future = asyncio.Future()
+print('future:', future, hex(id(future)))
+tasks = [asyncio.async(a(future))]
+
+res = loop.run_until_complete(b())
+