rua_obj was skipped because that looks to be a bit more work and should
be a separate commit.
This is to avoid the stack getting mangled when calling progs functions
with parameters.
This is part of the work for #26 (Record resource pointer with builtin
function data). Currently, the data pointer gets as far as the
per-instance VM function table (I don't feel like tackling the job of
converting all the builtin functions tonight). All the builtin modules
that register a resources data block pass that block on to
PR_RegisterBuiltins.
This will make it possible for the engine to set up their parameter
pointers when running Ruamoko progs. At this stage, it doesn't matter
*too* much, except for varargs functions, because no builtin yet takes
anything larger than a float quaternion, but it will be critical when
double or long vec3 and vec4 values are passed.
For now, just bsearch (normal and fuzzy), qsort, and prefixsum (not in
C's stdlib that I know of, but I think having native implementations of
float and int prefix sums will be useful.