rename octave::build_env namespace from octave::config * build-env-features.sh: Rename from ocgt-conf-features.sh. Update for new names. * build-env.h: Rename from oct-conf.h. Also declare features function. * build-env.in.cc: Rename from oct-conf.in.cc. * oct-conf-features.h: Delete. * libinterp/module.mk: Update. * toplev.cc, __init_gnuplot__.cc, octave.cc: Update for new names.

# scope1.m
function scope1 (n)
  value = n;
  if value
    C;
  end
  function A
    B;
    function B
      scope1 (0);
    endfunction
  endfunction

  function C
    D;
    function D
      A;
    endfunction
  endfunction
endfunction