Fix Config warning

Uses new syntax, but commented out for no warnings.

Supercedes atomvm#42

Signed-off-by: Peter M <[email protected]>

Author: petermm

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 Config
 
 # This configuration is loaded before any dependency and is restricted
 # to this project. If another project depends on this project, this
@@ -27,4 +27,4 @@ use Mix.Config
 # Configuration from the imported file will override the ones defined
 # here (which is why it is important to import them last).
 #
-#     import_config "#{Mix.env()}.exs"
+#     import_config "#{config_env()}.exs"