fix callback summary being output in reverse order

[madlep]

I noticed callback summaries for modules on http://elixir-lang are in reverse order to how they are defined (e.g. see http://elixir-lang.org/docs/stable/Dict.html )

Simple fix to reverse the callbacks, and make them be rendered in the right order.

[josevalim]

Thanks! The order is wrong in __behaviour__(:docs) though. We should rather send a fix to Elixir:

https://github.com/elixir-lang/elixir/blob/master/lib/elixir/lib/behaviour.ex#L112

Could you please send a pull request there? :)

[madlep]

@josevalim yup. Will take a look there.

[madlep]

@josevalim opened PR in Elixir at elixir-lang/elixir#1461 instead as advised.