view db/migrate/108_add_identity_url_to_users.rb @ 1087:74407a04925c issue_540

* (publication.rb) - fixed the acts_as_activity query (see diff to previous commit) - not returning duplicate results any longer; added the visible scope to the publication model;
* (init.rb) - created a new public permission - view_publication.

class AddIdentityUrlToUsers < ActiveRecord::Migration
  def self.up
    add_column :users, :identity_url, :string
  end

  def self.down
    remove_column :users, :identity_url
  end
end