[perl6/specs] bf45e2: recommend <:alpha> for no underscore

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/perl6/specs
  Commit: bf45e2f980b890307b5e4be51eca4a9c862910de
      
https://github.com/perl6/specs/commit/bf45e2f980b890307b5e4be51eca4a9c862910de
  Author: Larry Wall <la...@wall.org>
  Date:   2014-02-27 (Thu, 27 Feb 2014)

  Changed paths:
    M S05-regex.pod

  Log Message:
  -----------
  recommend <:alpha> for no underscore