Quick-hit updates

Changed the order of the Min/ Max UITextFields on the
SearchViewController.

Moved the “loadData()” func call from the viewDidAppear to the
viewDidLoad func in the ListingTableViewController. This way, the
UITableView loads only when “Home” first appears, and when the user
pulls to refresh. This should much of the issues where the user may
select the “Back” option from viewing the ListingDetailViewController
and quickly selecting another listing — crashes the app because the
asynchronous call to load the data is still being performed.

Also, changed the constraints on the priceLabel of the
ListingDetailViewController so that it isn’t limited by the trailing
constraint that once existed. (For longer prices, the label did not
resize enough.)