adds basic search form and results page
Let user select distance via drop-down on home page

https://app.asana.com/0/5189012931969/5189012931958

The distanoce was initially hard-coded to 5 miles, and the user was
not able to select a different distance.

* Determine the distance in the controller via the params[:miles]
  passed by the select tag on the home page.

* Use an if statement to display search results based on whether or
  not an address was passed