show an infoWindow with all pantries per location, addresses #40

If a given location (lat/lng) has multiple pantries, pop up an info window with the different pantries listed.
Small styling and content changes to the multiple pantry popup, and the "no pantries found" message.
remove inline style
Merge pull request #53 from codeforboston/multiple_pantries_per_location

show an infoWindow with all pantries per location