Make FUNCTION a FUNCT alias (#1773)

This would get rid of the old FUNCTION, making it do what FUNCT
currently does instead, in order to improve the look and feel of
Rebol code. FUNCT would be retained for backwards compatibility.
See http://issue.cc/r3/1973 for details.
Replace FUNCT with FUNCTION

Improve code readability, and make FUNCT name optional.
Make CLOSURE a FUNCT for closures (#2002)

This would make CLOSURE like FUNCTION, gathering locals, to make
that locals gathering seem like the primary usage model for user
functions in Rebol, to make the language easier to use.

The old CLOSURE function is renamed to CLOS, to be like FUNC for
closures the way the function is already in practice.

See http://issue.cc/r3/2002 and http://issue.cc/r3/1973 for details.
Fix make-make.r for backwards compatibility up to at least R3 A111

Explicitly list local variables with /local instead of using FUNCTION
(nee FUNCT). This removes the only dependency of make-make.r on the
"new" FUNCTION behaviour, avoiding an unnecessary circular dependency.
make-make.r can now be run again even with older R3 builds (back to at
least R3 A111).