message: add annotation for segmentIgnoreThreshold setting in Path.js
diff: @@ -35,6 +35,9 @@ Path.prototype = {
  strokeContainThreshold: 5,
  + // This item default to be false. but in map series,
  + // in order to improve performance, this will be true,
  + // so the shorty segment won't be drew.
  segmentIgnoreThreshold: false,
  /**
  