Modify {children} macro to all for a labels parameter

This request is for an enhancement to the Children Macro. We use the children macro to pull in pages for feature requests and features, including excerpts. The issue that I am having is that we have specifications as child pages as well and I don't want to include those. It would be perfect if we could add labels as a parameter to the Children macro so that I can pull in pages that have the feature or feature_set label only.