Update dependecies (05-28-17)

requirements/base.txt

 Django>=1.11
 django-autoslug==1.9.3
-django-cas-client==1.2.0
-djangorestframework==3.6.2 
-django-model-utils==2.6.1
+django-cas-client==1.3.0
+djangorestframework==3.6.3
+django-model-utils==3.0.0
 mysqlclient==1.3.10

requirements/test.txt

 # Test dependencies go here.
 -r base.txt
-coverage==4.3.4
+coverage==4.4.1