normalizePath(path) {
    path = relative(this.dest || this.basePath, path);
    if ('\\' == sep) {
      path = path.replace(/^[a-z]:\\/i, '/')
        .replace(/\\/g, '/');
    }
    return path;
  }
Normalize the given `path`.

@param {String} path
@return {String}
@api private