Changed the 'user' variable to 'get_user'

Changed the 'user' variable to 'get_user' instead due to https://docs.djangoproject.com/en/1.5/ref/templates/api/#django-contrib-auth-context-processors-auth

Because if you wanted to customize the app abit and let users see other users friends using the 'user' variable you will be logged in as the other user due to django's use of the variable 'user'.