Use wait_for for waiting a process with python 3.5

gns3server/utils/asyncio/__init__.py

@@ -77,12 +77,15 @@ def wait_for_process_termination(process, timeout=10):
     :param timeout: Timeout in seconds
     """
 
-    while timeout > 0:
+    if sys.version_info >= (3,5):
-        if process.returncode is not None:
+        yield from asyncio.wait_for(process.wait(), timeout=timeout)
-            return
+    else:
-        yield from asyncio.sleep(0.1)
+        while timeout > 0:
-        timeout -= 0.1
+            if process.returncode is not None:
-    raise asyncio.TimeoutError()
+                return
+            yield from asyncio.sleep(0.1)
+            timeout -= 0.1
+        raise asyncio.TimeoutError()
 
 
 @asyncio.coroutine