Scheduled weekly dependency update for week 00 (#124)

* Update pytest from 3.2.5 to 3.3.1

* Update aiohttp-session from 1.2.1 to 2.1.0

* Update aiohttp from 2.3.3 to 2.3.7

* Update pytest-aiohttp from 0.1.3 to 0.3.0

Author: pyup.io bot

requirements-dev.txt

@@ -1,14 +1,14 @@
 -e .
 flake8==3.5.0
-pytest==3.2.5
+pytest==3.3.1
 pytest-cov==2.5.1
 coverage==4.4.2
 sphinx==1.6.5
 pep257==0.7.0
-aiohttp-session==1.2.1
+aiohttp-session==2.1.0
 aiopg[sa]==0.13.1
 aioredis==1.0.0
 hiredis==0.2.0
 passlib==1.7.1
-aiohttp==2.3.3
-pytest-aiohttp==0.1.3
+aiohttp==2.3.7
+pytest-aiohttp==0.3.0