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/README.md

@@ -1,6 +1,6 @@
 # How to run the examples locally
 
 $ cp -r ./modules/playground ./dist/all/
-$ tsc -p modules --emitDecoratorMetadata -w
+$ ./node_modules/.bin/tsc -p modules --emitDecoratorMetadata -w
 $ gulp serve
 $ open http://localhost:8000/all/playground/src/hello_world/index.html?bundles=false