only run elixir code

ignore, for example, editor swapfiles

lib/watcher.ex

@@ -13,6 +13,7 @@ defmodule Watcher do
   end
 
   defp reload(file) do
+    if Path.extname(file) == ".ex" do
       try do
         file
         |> normalize
@@ -25,6 +26,7 @@ defmodule Watcher do
         e -> Display.show_compile_error(e)
       end
     end
+  end
 
   defp normalize(file) do
     String.replace_suffix(file, "___jb_tmp___", "")