tuple_format_new has lots of arguments, all of them necessary
indeed. But a small analysss showed that almost always there are
only two kinds of usage of that function: with lots of zeros as
arguments and lots of values taken from space_def.

Make two versions of tuple_format_new:
simple_tuple_format_new, with all those zeros omitted, and
space_tuple_format_new, that takes space_def as an argument.

NO_DOC=refactoring
NO_CHANGELOG=refactoring