message: src/reporter: log helpful message when request package is not installed
diff: @@ -13,7 +13,9 @@ export default function report(notice: Notice, opts: ReporterOptions): Promise<N
  let request;
  try {
  request = require('request');
  - } catch (_) {}
  + } catch (_) {
  + console.log('airbrake-js: please install request package');
  + }
  let utime = Date.now() / 1000;
  if (utime < rateLimitReset) {
  