Create a rough draft db design

[amlcheung]

1. Hardcode categories/dishes, "avgRatingForDish" will need to be consistently updated as users post their review--> see issue for the hardcoded data #25
2. design does not include slurper status yet --> waiting till that's figured out
3. 4 tables: users_slurp, posts, dishes, cuisines
4. "posts" is the ntermediate table that will have attributes that match fields in the users_slurp and dishes tables so that related information can be accessed
5. for the dishes table, an alternative design can be category (cuisine), dish > restaurantName