Add Set Building from Pair

[jdunkerley]

Given two columns of data A, B want to be able to construct sets where each pair defines a membership using transitive equality.

E.g.

A,B
B,C
B,D
E,F
E,G
G,H

Becomes:

A: A,B,C,D
E: F,G,H

Result should be a members value as the name (e.g. A and E in example above).

Adds a single column.

Table.add_set_from_pairs
    first:Column
    second:Column
    as:Text="Set"
    -> Table