Update pytz from 2016.10 to 2017.2

Author: pyup-bot

project/requirements/base.txt

@@ -28,7 +28,7 @@ git+git://github.com/mozilla/unicode-slugify#egg=unicode-slugify==0.1.3-HEAD
 django-autoslug==1.9.3
 
 # Time zones support
-pytz==2016.10
+pytz==2017.2
 
 # Your custom requirements go here
 django-bootstrap3==7.1.0