Clean up code. Add error pages.

Add:
	templates/error/(404, 500).html
		-add content to error pages; instead of rendering an error image, opted
		for plain text message. Looks sleeker.

	static/css/style.css
		-styling for error pages.

Mod:
	app.py, py(citi_bike, google_places).py
		-clean up code, removing print statements used for debugging and
		breaking up exceedingly lengthy lines.