Improve hints or explanations to setup resources

This comes from the feedback of a user, which was not able to setup the codes/computer easily. He just went to the setup resources page, then he arrived at the point of code name, and he thought it was sufficient. He went back to the calculations settings, he just submitted with localhost, failing the calculations (xps).

We need to put more information on this. This can be just a blue banner, or extensive explanation. Something the user will for sure read before attempting to do something with codes which are not yet set in his AiiDA setup.