For files with regions of numbers and other characters, it's intuitive
to have the numbers sorted by increasing numeric value rather than by
ASCII code. (Jeff Atwood has a nice article here:
https://blog.codinghorror.com/sorting-for-humans-natural-sort-order/)
For example, the listing for a directory containing `foo1`, `foo2`, and
`foo10` would sort in that order, rather than putting `foo10` between
`foo1` and `foo2`.
Closes#7226
