Document all hooks and how to use them

Did you verify this is a real problem by searching Stack Overflow and the other open issues in this repo?

Yes, the current hooks documentation does not describe all hooks and use-cases. Also the link in https://github.com/NativeScript/nativescript-cli/blob/master/README.md#extending-the-cli is broken.

Tell us about the problem

We need to document all hooks for CLI and how the plugins and users can get benefit of them.

Tasks:

• Fix the link in https://github.com/NativeScript/nativescript-cli/blob/master/README.md#extending-the-cli
• Document all hooks and when they are executed.
• Describe how to use the hooks and add examples.
• Add tests that verify the examples in the previous step work correctly and will not be broken in future release.

Comece pela seção “Extending the CLI” do README da CLI e pelo link quebrado nela. Faça um inventário dos hooks e de seus pontos de execução e, em seguida, documente seu uso e exemplos para plugins e usuários. Adicione testes que exercitem os exemplos documentados e confirmem que eles continuam funcionando.