code: function buildIconsObject(svgFiles, getSvg) {
    return svgFiles
      .map(svgFile => {
        const name = path.basename(svgFile, '.svg');
        const svg = getSvg(svgFile);
        const contents = getSvgContents(svg);
        return { name, contents };
      })
      .reduce((icons, icon) => {
        icons[icon.name] = icon.contents;
        return icons;
      }, {});
  }
docs: Build an object in the format: `{ <name>: <contents> }`.
  @param {string[]} svgFiles - A list of filenames.
  @param {Function} getSvg - A function that returns the contents of an SVG file given a filename.
  @returns {Object}