equivalent to --time=atime, not --time=ctime.
(ls invocation, du invocation): Fix typo: --time-style=long-iso
is equivalent to a time style with a leading "+".
(du invocation): --last-time is now --time.
--time-style no longer implies --time.
The locale and posix- stuff now works only for TIME_STYLE, not
for --time-style. Give equivalent format for --time-style=iso.
(Conditional Executability, Numeric Modes):
These days the sticky bit is more often uses as the restricted
deletion flag, so modernize the discussion about this.
(Mode Structure): Linux/GNU -> GNU/Linux.
(Symbolic Modes): Don't imply that "+ur" or "u" is valid.
(Setting Permissions): Don't imply that "+t" is invalid.
Use "rwx" rather than the less-common "rxw" in an example.
(Copying Permissions): Say that ugo is a replacement for
a string of the other letters. Add spaces around examples.
Use "set-user-ID" rather than "set user ID" to avoid ambiguity.
Use "+t" rather than "o+t", since POSIX doesn't specify the latter.
Mention which combinations are portable and which are GNU.
(Numeric Modes): Don't imply they aren't portable; they are
nowadays.
since it now works the same regardless of POSIX version.
(od invocation): -w N -> -w[N].
(pr invocation): -S STRING -> -SSTRING.
(fold invocation): -WIDTH works even when conforming to POSIX
1003.1-2001.
(head invocation, tail invocation): Likewise for -NUM.
(split invocation): Likewise for -LINES.
(uniq invocation): Likewise for -N.
(expand invocation, unexpand invocation): Likewise for -TAB.
(nice invocation): Likewise for -ADJUSTMENT.
(sort invocation): Clarify explanation of +N option.
(uniq invocation): Likewise.
(join invocation): Remove special case for --help, --version.
(touch invocation): Clarify explanation of date options.
(Options for date): -I timespec -> -I[timespec].
