UI to Support Creation of Matching Lists

Most of the awesome UI needed for the paired list creator should be able to be applied to building two lists at once with matching elements. Having matching lists like this is important whenever matching up multiple different kinds of input files corresponding to the same initial sample/replicate/etc....

A use case and work arounds are outlined here https://biostar.usegalaxy.org/p/22524/.

Alternatively, one might imagine the data flow would be better captured by record types (xref #3834) - I'm ambivalent on that point but I do believe Galaxy should provide robust UIs to cover either data flow pattern.

No files, tests, or entry points are named in the issue. Start by reviewing the existing paired-list creator UI and the use case and workarounds at https://biostar.usegalaxy.org/p/22524/, then clarify whether matching lists or record types are in scope; done requires an agreed design and a working UI for the selected data flow.

Written by the indexing model from the issue text.