Add man page description for version and help

[pauamma_gundo.com]

Is it worth saying whether diff3 --help and diff3 --version output to stdout or stderr?

GNU diff3 has -v as a --version alias. Does the replacement want/have that? If so, should be added to the manual page.

usr.bin/diff3/diff3.1

40

You should be able to use .Nm only after the first time. This is in fact recommended. https://docs.freebsd.org/en/books/fdp-primer/manual-pages/#manual-pages-sample-structures.

48

[thj]

In D35325#800913, @pauamma_gundo.com wrote:

Is it worth saying whether diff3 --help and diff3 --version output to stdout or stderr?

GNU diff3 has -v as a --version alias. Does the replacement want/have that? If so, should be added to the manual page.

I'm not adding short flags for these. They are requested so build systems can integrate and the long option isn't a cost there.

[thj]

• Don't user diff3 and Nm
• bump date

[pauamma_gundo.com]

Manual page English LGTM.