code: function isHidden(collection, pattern, patternKey) {
    return (
      (collection.hidden && collection.hidden.indexOf(patternKey) !== -1) ||
      (pattern.data && pattern.data.hidden)
    );
  }
docs: Should this pattern be hidden per collection or pattern metadata?
  @param {Object} collection   Collection obj
  @param {Object} pattern      Pattern obj
  @param {String} patternKey
  @return {Boolean}