Add scope view for GradingSurveyGroup and set access checks. The access checks are now properly set for create, edit and show. To facilitate the scope view the access check have an extra check built in to ensure that a scope is actually present before cheking for an existing Program.

"""Multi-consumer multi-producer dispatching mechanism

Originally based on pydispatch (BSD) http://pypi.python.org/pypi/PyDispatcher/2.0.1
See license.txt for original license.

Heavily modified for Django's purposes.
"""

from django.dispatch.dispatcher import Signal