Guest and User Search Listings

* Add route for search#show
* Create search_result view
* search result and search form partials
* Create search results controller and add skip before action
* Add search link to main page

  https://trello.com/c/pHFdo6KK
I realize we're just querying on "city" for now, but can we make this say `:query` to be consistent with the following line?