Pin DRF dependencies to work with Django 1.8

Pin dependencies `djangorestframework<3.7` and
`django-filter<1.1` which are versions that work
with Django 1.8. Later versions produce mysterious
errors.

I had to apply these version constraints in a
nasty global way because I could not find a way
to specify the versions in setup.py that would
actually be respected by setuptools. And I really
tried.

I also had to apply the pinning in two places:
- setup.py for general usage and the go.sh
  environment
- requirements.txt for Travis CI builds.

Author: jmurty

requirements.txt

@@ -1,4 +1,5 @@
 djangorestframework<3.7  # Avoid JSONField errors with Django 1.8
+django-filter<1.1  # Avoid get_filter_name() errors with Django 1.8
 
 -e .[api,brightcove,dev,docs,django18,forms,project,search,test,events,collections]
 

setup.py

@@ -68,6 +68,13 @@ def find_packages(*paths):
         'requests',
         'unidecode',
         'bleach<2',  # Bleach 2 adds a dependency on html5lib>=0.99999999, which breaks our above requirement of html5lib==0.999
+
+        # Django 1.8-specific version dependencies that must be here to be
+        # respected. Ideally these restrictions would go below in the
+        # 'django18' section but setuptools does not respect them there.
+        # TODO Remove these once GLAMkit uses Django > 1.8 by default.
+        'djangorestframework<3.7'  # Avoid JSONField errors with Django 1.8
+        'django-filter<1.1',  # Avoid get_filter_name() errors with Django 1.8
     ],
     extras_require={
         'api': [