[PATCH 3 of 6] exchange: add afterpush pyhook

[Matt Mackall]

On Sat, 2014-07-12 at 13:12 -0700, Gregory Szorc wrote:
>          # Maps names to list of callables.
> -        self._hooks = {}
> +        self._hooks = {
> +            'afterpush': [],
> +        }

Seems like we should handle missing entries instead.

-- 
Mathematics is the supreme nostalgia of our time.