function addFixtureFilesBase(spriter, files, cwd, resolvePaths) {
  for (const file of files) {
    const filePath = path.join(cwd, file);
    spriter.add(
      resolvePaths ? path.resolve(filePath) : file,
      file,
      fs.readFileSync(filePath, 'utf8')
    );
  }
}
Add a bunch of SVG files

@param {SVGSpriter} spriter        Spriter instance
@param {Array} files               SVG files
@param {string} cwd                Working directory
@param {boolean} resolvePaths      Whether to resolve the paths of SVG files