Convert gen_app_yaml.py to optparse
This allows for example the -f flag to be specified as the second
argument. Also add a '-i|--interactive' flag which asks for the
application name interactively.
"""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