Add citi_bike json scraping; add config.

Add:
	py/citi_bike.py
		-add citi_bike json scraping; get_json() will be used to
		periodically update the local mongo'd list of bike stations.

	py/config.py
		-will contain all configuration variables for our app; precludes
		having to initialize all values inside py/__init__.py, thereby
		promoting cleaner code.

Mod:
	py/__init__.py
		-add some basic import statements, and integrate app.config
		population from py/config.py.