code: public void addContent(String path, ContentElement content) throws IOException {
      String fullPath = buildJcrPathForZip(path) + "/" + DOT_CONTENT_XML;
      Document doc = xmlContentBuilder.buildContent(content);
      writeXmlDocument(fullPath, doc);
    }
docs: Add some JCR content structure directly to the package.
  @param path Full content path of content root node.
  @param content Hierarchy of content elements.
  @throws IOException I/O exception