fix(core): update

ts/smartrx.plugins.rxjs.ts

@@ -1,10 +1,6 @@
 // this file is intended to keep the bundle size down
 
-export {
-  Observable,
-  Subject,
-  fromEvent
-} from 'rxjs';
+export { Observable, Subject, fromEvent, ReplaySubject } from 'rxjs';
 
 import { startWith, takeUntil, map } from 'rxjs/operators';