Scheduled weekly dependency update for week 12 (#262)

* Update sphinx from 1.7.1 to 1.7.2

* Update cryptography from 2.2 to 2.2.1

* Update docker from 3.1.1 to 3.1.4

* Update pytest from 3.4.2 to 3.5.0

* Update aiohttp from 3.0.9 to 3.1.0

Author: pyup.io bot

requirements-dev.txt

@@ -1,18 +1,18 @@
 attrs==17.4.0
 flake8==3.5.0
-sphinx==1.7.1
+sphinx==1.7.2
 pep257==0.7.0
 -e .
 aioredis==1.1.0
-cryptography==2.2
-docker==3.1.1
+cryptography==2.2.1
+docker==3.1.4
 pynacl==1.2.1
-pytest==3.4.2
+pytest==3.5.0
 pytest-aiohttp==0.3.0
 pytest-cov==2.5.1
 pytest-mock==1.7.1
 pytest-sugar==0.9.1
-aiohttp==3.0.9
+aiohttp==3.1.0
 multidict==4.1.0
 chardet==3.0.4
 yarl==1.1.1