Code changes for https://github.com/icy-arctic-fox/spectator/issues/47 caused a drastic increase in compilation times.
This improves compilation times by splitting concerns for arguments.
In one case, arguments are used for matching.
In the other, arguments are captured for comparison.
The second case has been moved to a FormalArguments class.
Theoretically, this reduces the complexity and combinations the compiler might be iterating.
Undefined double methods were reporting splat arguments, which is technically correct.
But for output in these cases, it makes more sense to show the exact calling args.
