fix: don't move modules back to their "proper" location

The function modified here is meant to return `nil` when a file
shouldn't be removed. This was returning the "proper location" when it
should have just been returning `nil`, to indicate not to move the file.

fixes #159

lib/igniter.ex

@@ -1534,7 +1534,7 @@ defmodule Igniter do
     igniter.moves
     |> Enum.sort_by(&elem(&1, 0))
     |> Enum.map(fn {from, to} ->
-      [:red, from, :reset, ": ", :green, to]
+      [:red, Path.relative_to_cwd(from), :reset, ": ", :green, to]
     end)
     |> display_list("These files will be moved:")
   end

lib/igniter/project/module.ex

@@ -445,18 +445,15 @@ defmodule Igniter.Project.Module do
                 List.starts_with?(Path.split(path), Path.split(inside_matching_folder_dirname))
               end)
 
-            should_use_inside_matching_folder? =
-              if opts[:move_all?] do
-                dir?(igniter, inside_matching_folder_dirname) || just_created_folder?
-              else
-                source.path == proper_location(igniter, module, location_type) &&
-                  !dir?(igniter, inside_matching_folder_dirname) && just_created_folder?
+            if opts[:move_all?] || Rewrite.Source.from?(source, :string) do
+              if dir?(igniter, inside_matching_folder_dirname) || just_created_folder? do
+                inside_matching_folder
               end
-
-            if should_use_inside_matching_folder? do
-              inside_matching_folder
             else
-              proper_location
+              if source.path == proper_location(igniter, module, location_type) &&
+                   !dir?(igniter, inside_matching_folder_dirname) && just_created_folder? do
+                inside_matching_folder
+              end
             end
 
           :outside_matching_folder ->