Also, remove `plnkr.json` for `service-worker-getting-started` guide,
since it is not used and ServiceWorker cannot work correctly in
plnkr/stackblitz anyway (e.g. no build step to re-compute hashes).
A zipper might be useful and can be added in a subsequent PR, but it is
currently broken (e.g. no dependency on `@angular/service-worker`).
PR Close#20165
This commit was worked on by a number of people including
@filipesilva, @gkalpak and @wardbell. It contains changes that:
* remove unused files,
* fix the bootstrap approach to ensure that bootstrap is in the correct Zone
* fix unclosed code-example tags
* replace use of "we" with "you"
* remove broken dual router example
Related to angular/angular.io#3541
Brandon Roberts
Rafael
Igor Minar
Kapunahele Wong
George Kalpakas
Jesus Rodriguez
Peter Bacon Darwin