Document r315433, libarchive 3.3.1.
Document r316958, tcsh 6.20.00.
Document r310490, amd(8) 6.2.
Document r316350, tzdata 2017b.
Document r309848, file(1) 5.29.
Document r309512, Subversion 1.9.5.
Document r312516, xz(1) 5.2.3.
Prune comments.
Bump copyright year.

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