/// <summary>
 /// Adds <paramref name="blockElementParser"/> to the end of the block elements parsing chain.
 /// </summary>
 /// <param name="blockElementParser"></param>
 public void AddBlockElementParser(IBlockElementParser blockElementParser)
 {
     lock (syncRoot)
     {
         AddElementParser(rootBlockElementParser, blockElementParser);
     } // lock
 }
 /// <summary>
 /// Adds <paramref name="blockElementParser"/> to the <paramref name="authoringEngine"/>.
 /// </summary>
 /// <param name="authoringEngine"></param>
 /// <param name="blockElementParser"></param>
 protected virtual void AddBlockElementParser(IAuthoringEngine authoringEngine,
                                              IBlockElementParser blockElementParser)
 {
     authoringEngine.AddBlockElementParser(blockElementParser);
 }