Fix config usage

Author: wkirschbaum

config/config.exs

@@ -1,6 +1,6 @@
 # This file is responsible for configuring your application
 # and its dependencies with the aid of the Mix.Config module.
-use Mix.Config
+import Mix.Config
 
 # This configuration is loaded before any dependency and is restricted
 # to this project. If another project depends on this project, this