Frames-map-reduce

Frames wrapper for map-reduce-folds and some extra folds helpers.

Frames-map-reduce provides some helpers for using the map-reduce-folds library with vinyl records and Frames. These include functions for filtering Frames, splitting records into key columns and data columns and recombining key columns with other columns after reducing. This package also provides some tools for building folds over records from folds over each column, e.g, summing multiple numerical columns into a multi-column result.