Update requirements and use Pipfile to manage explicit pinning

Currently our requirements are out of date and we don't know what is
pinned for an explicit reason. Using pipfile we can keep them pinned
but update easily

Pipfile

@@ -0,0 +1,27 @@
+[[source]]
+url = "https://pypi.python.org/simple"
+verify_ssl = true
+
+[packages]
+amqp = ">=2.1.4"
+celery = ">=4,<5"
+Django = ">=1.10,<1.11"
+djangorestframework = ">=3.5,<3.6"
+django_polymorphic = "*"
+django-jsonify = "*"
+django-filter = "*"
+django_compressor = "*"
+django-auth-ldap = "*"
+anyjson = "*"
+dj-database-url = "*"
+freezegun = "*"
+gevent = "*"
+gunicorn = "*"
+icalendar = "*"
+psycopg2 = "*"
+python-dateutil = "*"
+pytz = "*"
+redis = "*"
+requests = "*"
+twilio = "*"
+whitenoise = "*"

requirements.txt

@@ -1,34 +1,35 @@
-amqp<3.0,>=2.1.4
+amqp==2.1.4
 anyjson==0.3.3
-argparse==1.2.1
-celery>=4,<5
+appdirs==1.4.3
+billiard==3.5.0.2
+celery==4.0.2
 dj-database-url==0.4.2
+Django==1.10.6
 django-appconf==1.0.2
-django-auth-ldap==1.2.6
+django-auth-ldap==1.2.10
 django-compressor==2.1.1
 django-filter==1.0.1
 django-jsonify==0.3.0
-django-mptt==0.6.0
 django-polymorphic==1.1
-Django>=1.10,<1.11
-djangorestframework>=3.5,<3.6
+djangorestframework==3.5.4
 freezegun==0.3.8
-gevent==1.0.1
-gunicorn==19.6.0
-httplib2==0.7.7
-icalendar==3.2
-Markdown==2.5
-ndg-httpsclient==0.4.2
-psycogreen==1.0
-psycopg2==2.5.1
-pyasn1==0.1.9
-PyJWT==0.1.2
-pyOpenSSL==16.1.0
-python-dateutil==2.1
-pytz==2014.10
-redis
-requests==2.7.0
-twilio==3.4.1
+gevent==1.2.1
+greenlet==0.4.12
+gunicorn==19.7.0
+httplib2==0.10.3
+icalendar==3.11.3
+kombu==4.0.2
+packaging==16.8
+psycopg2==2.7
+pyparsing==2.2.0
+python-dateutil==2.6.0
+python-ldap==2.4.32
+pytz==2016.10
+rcssmin==1.0.6
+redis==2.10.5
+requests==2.13.0
+rjsmin==1.0.12
+six==1.10.0
+twilio==5.7.0
 vine==1.1.3
 whitenoise==3.3.0
-wsgiref==0.1.2