so recursion depth is limited only by the process stack limit.
reorganizing evaluator so the same code is used for evaluating
and pushing arguments for both builtin functions and lambdas.
for now this is slower, but it was done in preparation for
Things To Come.
adding list-head
implementing the calling convention for long argument lists in
bytecode compiler. arguments are broken down into a nest of
list and nconc calls.
also implementing vararg builtins.
JeffBezanson