move various angular bits into shared jslib

src/angular/directives/stop-prop.directive.ts

@@ -0,0 +1,13 @@
+import {
+    Directive,
+    HostListener,
+} from '@angular/core';
+
+@Directive({
+    selector: '[appStopProp]',
+})
+export class StopPropDirective {
+    @HostListener('click', ['$event']) onClick($event: MouseEvent) {
+        $event.stopPropagation();
+    }
+}