function generateIndex(files, options) {
  gutil.log(' ', 'Generating index page...');
  let context = {
    description: options.description,
    section: options.section,
    articles: files,
  };
  if (options.title) {
    context.title = options.title;
  }
  let template = path.join(global.WF.src.templates, 'index.yaml');
  if (options.template) {
    template = options.template;
  }
  let outputFile = path.join(options.outputPath, '_index.yaml');
  if (options.outputFile) {
    outputFile = options.outputFile;
  }
  renderTemplate(template, context, outputFile);
}
Generate an index page

@param {Array} files List of files to generate page for
@param {Object} options Options used to generate the page