Towards taking care of safe / unsafe ppmpf tuples.

A rather complicated commit, aiming towards deprecating the older recursive
expansion macro construct. Safe and unsafe ppmpf tuples have separate fold,
map, zip, zipwith high order macros. The addition of recursively expanding
"double" folding construct targets self - reentrant issues when multiple
"higher order" macro functions are combined with ppmpf tuples.
Cleaning up previous fold implementations in ppmpf.
Several changes to ppmpf sequences, resolves #1

The new recursive expansion construct is used; folding, mapping and to tuple
transformation fixed accordingly.