[wpilib] Add SmartDashboard::PutData() reference overload

[calcmogul]

No description provided.

[PeterJohnson]

Historically we used a pointer here to indicate that the lifetime of the passed-in object mattered (e.g. because we store that pointer and call it later). It makes it at least somewhat more obvious that you should think about the lifetime of the thing you're passing (e.g. you shouldn't pass a local variable). What's the advantage of having the reference overload?

[calcmogul]

Historically we used a pointer here to indicate that the lifetime of the passed-in object mattered

I highly doubt our target audience is picking up on that nuance, especially since we don't explain that convention anywhere.

What's the advantage of having the reference overload?

The same advantages of providing reference overloads for constructors: it's more idiomatic, and our users don't have to remember to spam prefix ampersands to get their code to compile.