add map thumbnail and summary table to project detail page

[smcalilly]

Overview

Closes #149

Demo

Testing Instructions

• fetch this branch (still no heroku review apps)
• follow steps in the readme to load the gis and fixture data
• you'll have to add some assets to a phase
• make sure the map thumbnail and table loads on the project detail page
• also make sure it doesn't load if you're looking at a project that has no assets