added red heart image
toggle like button when user likes/unlikes post
api requests for liking and unliking posts
send api request after liking or unliking post
added date label to post view controller
added timestamp and formatted date properties
removed commented out code
added shared date formatter object to avoid reallocating a lot
added months array to date formatter
parse timestamp into formatted date string
show formatted date in post view
used shared date formatter to parse timestamp
update nearby button with city, state whenever location is determined.
show error alert on main thread
clear title and message of loading indicator when dismissed