Code review

I wanted to give you some input on what you have so far. 
 * Provide example config files for other developers (.env, config/database.yml).
 * Having a unique index on city name will be problematic.
 * Keep your factories simple. Don't use `rand(n)`. Drop your test db after making these changes.
 * Avoid using `_id or .id`. Use the active record object instead.
It would be really cool, and useful, if you could make a factory that created a map with photos. Then, you could: 

```
map = FactoryGirl.create(:map_with_photos)
sign_in_as(map.user)
# expect to find map.photos.first in the page
```
Check out the has_many example using after(:create): https://github.com/thoughtbot/factory_girl/blob/master/GETTING_STARTED.md#associations

It might also be useful to set up factory linting: 
https://github.com/thoughtbot/factory_girl/blob/master/GETTING_STARTED.md#linting-factories