Make implicit minimum Tornado version explicit

TornadoTransportTests.test__sending_successfully_calls_success_callback uses gen.maybe_future, which appeared in Tornado 4.0
TornadoAsyncClientTestCase.test_sending_to_unresponsive_sentry_server_logs_error and TornadoTransportTests.test__sending_with_error_calls_error_callback use gen.sleep, which appeared in Tornado 4.1

1 files changed, 1 insertions, 1 deletions

diff --git a/setup.py b/setup.py
index 013698b..d14bea7 100755
--- a/setup.py
+++ b/setup.py
@@ -69,7 +69,7 @@ tests_require = [
     'pytest-django==2.9.1',
     'pytest-timeout==0.4',
     'requests',
-    'tornado',
+    'tornado>=4.1',
     'webob',
     'webtest',
     'anyjson',