Converted $ macro to use variadic arguments. Added set: and mset: prefixes

[samgreen]

First off, awesome wizardry using the runtime and the new autoboxing to make this library. Really impressive!

I converted the $ macro to use __VA_ARGS__ to allow as many arguments as you'd like to the function. This was necessary for the set changes I added, otherwise the comma in the set object list confuses the compiler in to thinking it is a second parameter to the function.

Also added tests for these new items, as well as stringized tests to ensure they will be equivalent. We might want to move the code to the base block for cleaning stringized items. Open to feedback on this.

[dbachrach]

Awesome! Will take a deeper look and merge this in soon.