Scheduled weekly dependency update for week 30 (#307)

* Update sphinx from 1.7.5 to 1.7.6

* Update cryptography from 2.2.2 to 2.3

* Update docker from 3.3.0 to 3.4.1

* Update pytest from 3.6.1 to 3.6.4

* Update aiohttp from 3.3.1 to 3.3.2

* Update yarl from 1.2.5 to 1.2.6

Author: pyup.io bot

requirements-dev.txt

@@ -1,19 +1,19 @@
 attrs==18.1.0
 flake8==3.5.0
-sphinx==1.7.5
+sphinx==1.7.6
 pep257==0.7.0
 -e .
 aioredis==1.1.0
-cryptography==2.2.2
-docker==3.3.0
+cryptography==2.3
+docker==3.4.1
 pynacl==1.2.1
-pytest==3.6.1
+pytest==3.6.4
 pytest-aiohttp==0.3.0
 pytest-cov==2.5.1
 pytest-mock==1.10.0
 pytest-sugar==0.9.1
-aiohttp==3.3.1
+aiohttp==3.3.2
 multidict==4.3.0
 chardet==3.0.4
-yarl==1.2.5
+yarl==1.2.6
 aiomcache==0.6.0