Fibonacci series calculation performance boost using WebAssembly

Egads - these are the kinds of things you think up when you take a "frameworks-first" approach to things, I guess.

(By which I don't mean anything snarky, or anti-framework. But rather more simply: (1) Why the hell would you do these kinds of computations in such an environment? (2) There are much better ways of speeding up Fibonacci besides memoization).