Changed permissions are not reloaded

[alovak]

Thanks for an awesome gem!

I have found that when I change permissions changes are not applied in development environment. So I have to reload application (with spring / pow).

As far as I understand what should be done is following:

add to railtie

config.to_prepare do
  ActionAccess::Keeper.instance.reload
end

and add reload (or init or ...) to Keeper class.

Do you want me to create PR with this?