refactor(core): change module semantics

This contains major changes to the compiler, bootstrap of the platforms
and test environment initialization.

Main part of #10043
Closes #10164

BREAKING CHANGE:
- Semantics and name of `@AppModule` (now `@NgModule`) changed quite a bit.
  This is actually not breaking as `@AppModules` were not part of rc.4.
  We will have detailed docs on `@NgModule` separately.
- `coreLoadAndBootstrap` and `coreBootstrap` can't be used any more (without migration support).
  Use `bootstrapModule` / `bootstrapModuleFactory` instead.
- All Components listed in routes have to be part of the `declarations` of an NgModule.
  Either directly on the bootstrap module / lazy loaded module, or in an NgModule imported by them.

modules/playground/src/routing/app/inbox-detail.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Component, AppModule} from '@angular/core';
+import {Component, NgModule} from '@angular/core';
 import {ROUTER_DIRECTIVES, ActivatedRoute, provideRoutes} from '@angular/router';
 import {PromiseWrapper} from '@angular/core/src/facade/async';
 import {InboxRecord, DbService} from './inbox-app';
@@ -24,7 +24,8 @@ export class InboxDetailCmp {
   }
 }
 
-@AppModule({
+@NgModule({
+  declarations: [InboxDetailCmp],
   providers: [provideRoutes([{path: ':id', component: InboxDetailCmp}])]
 })
-export default class InboxDetailModule {}
+export default class InboxDetailModule {}

modules/playground/src/routing/index.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {InboxApp, ROUTER_CONFIG} from './app/inbox-app';
+import {InboxApp, InboxCmp, DraftsCmp, ROUTER_CONFIG} from './app/inbox-app';
 import {bootstrap} from '@angular/platform-browser-dynamic';
 import {HashLocationStrategy, LocationStrategy} from '@angular/common';
 import {provideRoutes, RouterModule} from '@angular/router';
@@ -17,6 +17,7 @@ export function main() {
       provideRoutes(ROUTER_CONFIG),
       {provide: LocationStrategy, useClass: HashLocationStrategy}
     ],
-    modules: [RouterModule]
+    declarations: [InboxCmp, DraftsCmp],
+    imports: [RouterModule]
   });
-}
+}