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.

scripts/ci-lite/offline_compiler_test.sh

@@ -3,7 +3,7 @@ set -ex -o pipefail
 
 # These ones can be `npm link`ed for fast development
 LINKABLE_PKGS=(
-  $(pwd)/dist/packages-dist/{common,core,compiler,compiler-cli,platform-{browser,server},platform-browser-dynamic}
+  $(pwd)/dist/packages-dist/{common,forms,core,compiler,compiler-cli,platform-{browser,server},platform-browser-dynamic}
   $(pwd)/dist/tools/@angular/tsc-wrapped
 )
 PKGS=(