message: append list item
diff: @@ -61,6 +61,25 @@ class Runner extends EventEmitter implements IPlatform {
  this.sharedString.insertText(value, 0);
  }
  + public appendListItem(item: string) {
  + let endMarker = this.sharedString.client.mergeTree.getSegmentFromId("endList");
  + if (!endMarker) {
  + const endProps = MergeTree.createMap<any>();
  + endProps[MergeTree.reservedTileLabelsKey] = ["pg"];
  + endProps[MergeTree.reservedMarkerIdKey] = "endList";
  + this.sharedString.insertMarker(0, MergeTree.ReferenceType.Tile, endMarker);
  + endMarker = this.sharedString.client.mergeTree.getSegmentFromId("endList");
  + }
  + const endPos = this.sharedString.client.mergeTree.getOffset(endMarker,
  + MergeTree.UniversalSequenceNumber, this.sharedString.client.getClientId());
  + this.sharedString.insertText(item, endPos);
  + const pgProps = MergeTree.createMap<any>();
  + pgProps[MergeTree.reservedTileLabelsKey] = ["pg", "list"];
  + pgProps.indentLevel = 1;
  + pgProps.listKind = 1;
  + this.sharedString.insertMarker(endPos, MergeTree.ReferenceType.Tile, pgProps);
  + }
  +
  private async start(runtime: IRuntime, platform: IPlatform) {
  const rootMapId = "root";
  const insightsMapId = "insights";
  