create navbar, user login, sessions
build further login signup functionality
Merge branch 'make-users'
add slug to User, find by sluggified username for sessions#create
make neighborhood show page work for signed in user
add non-functional favorite button
favoriting and un-favoriting works
Merge branch 'nycapi'
start user show page
fix bug with un-favoriting
get flickr url
add most neighborhood pictures from flickr, 20 missing
clean up comments
add missing photos and update user show page
fix picture for Carnegie Hill
recommend neighborhoods by median buy price
prevent favorite from being created when user_id is nil
hide favorite button if user is not in the database
ajaxify favorite button on neighborhood show page
added google map with neighboorhood