Add requirements.txt files for pip quick-installation.
Enable clickjacking protection and django admin in base.py settings file.
Make INSTALLED_APPS tuple the concatenation of DJANGO_APPS and THIRD_PARTY_APPS.
Create app skeletons for user_management, communications, and analytics.  Add these apps to the CUSTOM_APPS tuple in base.py settings file.
Merge branch 'initial_django_setup' into development