lloda/ra-ra: A C++20 array and expression template library with some J/APL features @ 6.3

lloda 8bffea70fb Rename Owned to Big		%!s(int64=7) %!d(string=hai) anos
..
Makefile	757833352d Settle for a meaning of ra_iterator (assign op) array-expr	%!s(int64=8) %!d(string=hai) anos
SConstruct	bc22b9f398 Refactor SConstruct and subs	%!s(int64=7) %!d(string=hai) anos
ra-ra.texi	8bffea70fb Rename Owned to Big	%!s(int64=7) %!d(string=hai) anos