REF: Use numpy arrays instead of appending to lists in bellman.

Performace was essentially identical.
ENH: Cythonize fminbound.
also part of cythonization.

Speedup of 14.8 -> 8.84
checking correctness.
BUG: beta was at .06; shld have been at .97
PERF: Cythonize whole optimization loop.
tack onto last change
PERF: Added numpy optimizations.
CLN:  Finishing up optimization round.