update from Atlas with major reorg

attic/concurrency/timer.py

@@ -0,0 +1,17 @@
+import asyncio
+
+@asyncio.coroutine
+def show_remaining():
+    for remaining in range(5, 0, -1):
+        print('Remaining: ', remaining)
+        yield from asyncio.sleep(1)
+
+def main():
+    loop = asyncio.get_event_loop()
+    try:
+        loop.run_until_complete(show_remaining())
+    finally:
+        loop.close()
+
+if __name__ == '__main__':
+    main()