Bug: man page and --help are not consistent

[zachriggle]

Thanks again @chmln for creating a neat tool -- and thanks for bothering to create a man page at all, it's a rarity for FOSS command line tools.

Currently, the --help and man sd output each have different details listed.

• --help is missing the EXAMPLES that the manpage has
• man is missing some of the list of valid values for --flags, and is not formatted well
• man and --help disagree on the names of the arguments (e.g. replace-with vs replace_with)
• --help is missing the return codes