parser: add binary support to determine_number_system and parse_size

[csko]

Adds support for binary number sizes.

One of the subtasks in https://github.com/uutils/coreutils/issues/7738 cc BenWiederhake

[sylvestre]

please add tests at the high level here: https://github.com/uutils/coreutils/edit/main/tests/by-util/test_du.rs

[github-actions[bot]]

GNU testsuite comparison:

Skipping an intermittent issue tests/misc/usage_vs_getopt (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)

[github-actions[bot]]

GNU testsuite comparison:

GNU test failed: tests/printf/printf-indexed. tests/printf/printf-indexed is passing on 'main'. Maybe you have to rebase?
Skipping an intermittent issue tests/misc/tee (passes in this run but fails in the 'main' branch)
Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)

[sylvestre]

please reopen when it is ready