Improve perf of f-order array operations

[bluss]

C-order is the default order. The following functions need adaption for f-order:

• map
• to_owned
• zip_mut_with broadcast from 0
• zip_mut_with general
• scalar_sum
• allclose
• eq

allclose, to_owned, map, scalar_sum can all start with implementing an agnostic version of as_slice()