Adding detector-project template to projects as a submodule

[jgalan]

We should take it as a good chance to review the base/template project for detector-project.

I use detector-project and not template-project because it might happen that in future we get other kind of project templates. This one is clearly intended for detectors.

Please, update this PR and take the opportunity for making contributions or suggestions to the base reference project.

@rest-for-physics/core_dev

[jgalan]

Plz, could this project submodule add-on be approved? It is only a submodule added, other changes are related to automatic formatting.

[jgalan]

@rest-for-physics/core_dev