Code Tour Suggestion: Use shell command for dotnet commands

[Jon Galloway]

I'm not sure this is a good idea, but if it works it would be nice to use the shell command syntax to allow executing the dotnet add package ... commands in the terminal rather than requiring the user to copy and paste them. This is kind of grunt work from the learner's perspective, it doesn't teach me EF concepts.

One possible downside is that the Code Tour docs says that this creates a new terminal window and executes the steps. This might not work well in the case where we're executing several commands, or could be confusing since we're already having them type some commands in a terminal window. But... if it does work well, I think it would be a better experience.

[Cam Soper]

@jongalloway Maybe I should have read the docs better! Yes, I think we should be using this.