add more data

[sfmorris]

• using the latest models.py, scrape yelp and petfinder api
• use the resulting json files to populate the database, either with fixtures or the json_insert_script.py script
• per Aseal, we need "a small handful of cities, a dozen shelters, and dozens of pets"

[sfmorris]

73 pets, 10 shelters, 5 cities