Merge pull request #459 from python-hyper/requires-io-2.4.X

[requires.io] dependency update on 2.4.X branch

Author: Lukasa

tox.ini

@@ -11,5 +11,5 @@ commands= py.test -n 4 h2 {toxinidir}/test/
 
 [testenv:lint]
 basepython=python3.4
-deps = flake8==3.2.1
+deps = flake8==3.3.0
 commands = flake8 --max-complexity 10 h2 test