PPMPF_MAP as a first ppmpf bind - aware prototype.

With the work done on PPMPF_BDS31, a ppmpf branching expression was used
in order for the PPMPF_TUP_MAP / PPMPF_UTUP_MAP to become bind - aware.
The newer macro is at its 3rd generation and is to be the prototype
upon which PPMPF_TUP_MAP, PPMPF_UTUP_MAP and PPMPF_SEQ_MAP are going to
be unified and become bind - aware. Affects series of dependent issues
#6, #9, #18, #20. The macro has its own dedicated test that can be
checked with 'make just ppmpf/map.cc'. This macro is going to be used
as the model upon which the other high order function emulators are
going to evolved into macros with "binding" and "type" features like the
left and right folds, zip, zipwith.