Revert default export

TypeScript does not automatically assign the only default export to exports, or at least not with my configuration. Not worth testing around, and this also makes it easier to use for normal JavaScript.

source/ratelimiter.ts

@@ -31,7 +31,7 @@ type RateLimiterExecutor = RateLimiterSyncExecutor | RateLimiterAsyncExecutor;
 /** A simple but effective way to rate limit Tasks.
  *
  */
-export default class RateLimiter {
+export class RateLimiter {
 	private _maximum: number = 0;
 	private _available: number = 0;
 	private _instances: any[];