Add ability to see custom enum values

[sosedoff]

Example query:

SELECT n.nspname AS "schema", t.typname, string_agg(e.enumlabel, '|' ORDER BY e.enumsortorder) AS enum_labels
FROM   pg_catalog.pg_type t 
JOIN   pg_catalog.pg_namespace n ON n.oid = t.typnamespace 
JOIN   pg_catalog.pg_enum e ON t.oid = e.enumtypid  
WHERE  t.typname = 'NAME'
GROUP  BY 1,2;

[tsbriggs02]

I came here to request this exact feature. I know, I can just issue the query above, but it would be great to have it in the UI...