Upgrade Django and psycopg2 to match base container (#813)

The base container has gotten some patch version upgrades and dependabot
is saying we should upgrade Django. Staying in sync with the base container
isn't strictly necessary, but seems like a good plan. So this does that,
and adjusts the comment in the requirements file to better describe the
situation.

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 #### Added
 - S3 caching of Census data files
+- Upgrade Django (2.2.10 -> 2.2.16) and psycopg2 (2.8.4 -> 2.8.5)
 
 ## [0.13.0] - 2020-02-14
 

src/django/requirements.txt

@@ -1,8 +1,11 @@
-# Django and psycopg2 are included in the django base container but repeated here
-# so that the analysis container will know to install them. These should be kept
-# in sync with the versions in the base container.
-Django==2.2.10
-psycopg2-binary==2.8.4
+# Django and psycopg2 are included in the django base container, but the analysis
+# container also needs them, and uses this same requirements file.
+# Which means the versions here will be the ones that get installed, in both places.
+# Ideally these should be kept in sync with the versions in the base container
+# (https://github.com/azavea/docker-django/blob/master/2.2/requirements.txt) to avoid
+# downgrading when building the django container.
+Django==2.2.16
+psycopg2-binary==2.8.5
 
 boto3==1.9.224
 django-amazon-ses==2.1.1