Update flake8 from 3.6.0 to 3.7.7

pyup-bot · pyup-bot · commit a1590908c7a3 · 2019-02-25T13:01:54.000-08:00
diff --git a/requirements_dev.txt b/requirements_dev.txt
@@ -2,7 +2,7 @@ pip==18.1
 bumpversion==0.5.3
 wheel==0.32.2
 watchdog==0.9.0
-flake8==3.6.0
+flake8==3.7.7
 tox==3.5.3
 coverage==4.5.1
 Sphinx==1.8.1
