remove.selection: Remove Selected Categories Per Location
In deanrobertevans/TrillR: Functions for Selecting Acoustic Recordings

This function removes all files that correspond to already selected files so that you can continue with file selction.

1	remove.selection(starting.data, selection.remove)

`starting.data`	A starting data.frame for which you want to remove recordings from. Must have a location and categorty column.
`selection.remove`	A data.frame that contains selections you want to remove from the starting data.frame. Must have a location and categorty column.