Basic onboading flow (#24)

* removed unused file

* [WIP] Created onboarding form

* Finished basic onboarding flow; added tests

* Improved onboarding language

lib/pinchflat/media.ex

@@ -100,6 +100,7 @@ defmodule Pinchflat.Media do
       field -> List.wrap(mapped_struct[field])
     end)
     |> List.flatten()
+    |> Enum.filter(&is_binary/1)
   end
 
   @doc """