function makeRe(glob, opts) {
  if (utils.typeOf(glob) !== 'string') {
    throw new Error(msg('makeRe', 'glob', 'a string'));
  }

  return utils.cache(toRegex, glob, opts);
}
Create and cache a regular expression for matching file paths.
If the leading character in the `glob` is `!`, a negation
regex is returned.

@param  {String} `glob`
@param  {Object} `options`
@return {RegExp}