Currently, the `readme.md` also contains information on how to build and test the CLI which isn't useful to most users. With this change we move this information into a seperate document.
I wrote down my understanding of the best ways to build/run/test/debug this repository.
A couple other random things included here:
* Removed an extraneous `debugger;` statement which I kept hitting.
* Removed the `watch` scripts which are no longer used and don't need to be supported.
* Removed `yarn test-cli-e2e`, as it alters the $PATH and can use the wrong `ng` instance.
Added types from the commit validation script to CONTRIBUTING. Added
packages names from the package script to the scope section. Added
examples of good commit messages.
Also corrected some texts.
