Adding pins to the map to show where instructors are (by closest
airport).  The airports_config.yml file is generated from admin data
and checked in here occasionally.  The code to toggle things
duplicates that used for toggling past bootcamps; that should be
refactored.
Merge pull request #33 from gvwilson/adding-instructor-locations-to-map

Adding pins to the map to show where instructors are