Add Google Maps Imagery to Power Plant Pages

[vkoves]

Google Maps has an API for pulling their imagery, so we should try and use it to pull imagery for each power plant page. A few things to consider:

1. We should make this a process you run manually - we want to run this basically once and choose to update it later if we update the power plant data
2. Make sure to pay attention to copyright and attribution - Google should have a policy on using Google Maps imagery, and it all lies in making clear that we're using their images
3. Money - Viktor or Derek can probably hook this up to their Google account since this will cost a bit (not much, but maybe a few bucks). We can limit this by only running it for large power plants (maybe > 100 MW?)

[vkoves]

It looks like the right place to go for these API docs: https://developers.google.com/maps/documentation/maps-static/start

We then need to setup an account here: https://console.cloud.google.com/google/maps-apis/discover

[vkoves]

Closed by #203