[perl6/specs] 8ece61: Mention ∅, clarify set composer semantics more

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/perl6/specs
  Commit: 8ece611462f2bb694dbaeee3e52713bf3b493242
      
https://github.com/perl6/specs/commit/8ece611462f2bb694dbaeee3e52713bf3b493242
  Author: Larry Wall <la...@wall.org>
  Date:   2013-09-26 (Thu, 26 Sep 2013)

  Changed paths:
    M S32-setting-library/Containers.pod

  Log Message:
  -----------
  Mention ∅, clarify set composer semantics more