code: async function buildPathsObject(files) {
    return Promise.all(
      files.map(async filepath => {
        const name = path.basename(filepath, '.svg');
        const svg = fs.readFileSync(filepath, 'utf-8');
        const pathStrings = await svgo.optimize(svg, { path: filepath })
          .then(({ data }) => data.match(/ d="[^"]+"/g) || [])
          .then(paths => paths.map(s => s.slice(3)));
        return `"${name}": [${pathStrings.join(',\n')}]`;
      }),
    );
  }
docs: Loads SVG file for each icon, extracts path strings `d="path-string"`,
  and constructs map of icon name to array of path strings.
  @param {array} files