core/tt_ind2sub.m, core/tt_sub2ind.m: vectorizations
cross/amen_cross.m: smart index/functional input
cross/multifuncrs2.m: just calls amen_cross
new file:   solve/alstpz_solve.m: ALS(t+z) implementation
solve/amen_solve2.m, solve/dmrg_solve3.m: testdata is populated only after the last block (mem savings).