First numba tests.

Experiment in implementing simulateDSM in Numba to improve performance.  Currently craters performance (37s on the test!), can't accept keyword arguments (just pass the values in the right place), plays badly with some type checking (disabled it), and I'm having trouble getting the second argument tuple specified correctly so I can specify all types instead of simply leaving it up to the library.

May work faster if I put individual JIT blocks in the function.  Consider this a long term work in progress.