close to array doubler. generated code is correct but ctypes type checking fails on numpy array
array doubler works!
doubler works for ints, floats, and double arrays
move numpy.dtype -> ctype mapping to ctree.types
enable 'static inline' on ArrayDoubler::apply function to trigger inlining. Bumped the optimization level to 3 so now the code auto-vectorizes. Huzzah!
get all examples working again