* NEWS: Document --no-check-device and --check-device.

* doc/rendition.texi: Change the way FIXME-*refs are handled in
!PROOF.
* doc/intern.texi, doc/tar.texi: Update.
* doc/untabify.el: New file.
* doc/Makefile.am (EXTRA_DIST): Add untabify.el
(untabify, final, check-format, check-refs, check-fixmes)
(check-unrevised, all-check-docs, check-docs): New rules.

doc/intern.texi

@@ -36,8 +36,6 @@ Archives are permitted to have more than one member with the same
 member name.  One way this situation can occur is if more than one
 version of a file has been stored in the archive.  For information
 about adding new versions of a file to an archive, see @ref{update}.
-@FIXME-xref{To learn more about having more than one archive member with the
-same name, see -backup node, when it's written.}
 
 In addition to entries describing archive members, an archive may
 contain entries which @command{tar} itself uses to store information.
@@ -108,11 +106,11 @@ group permission could be copied from the @emph{other} permission.
 
 The @code{uid} and @code{gid} fields are the numeric user and group
 @acronym{ID} of the file owners, respectively.  If the operating system does
-not support numeric user or group @acronym{ID}s, these fields should be ignored.
+not support numeric user or group @acronym{ID}s, these fields should
+be ignored. 
 
 The @code{size} field is the size of the file in bytes; linked files
-are archived with this field specified as zero.  @FIXME-xref{Modifiers, in
-particular the @option{--incremental} (@option{-G}) option.}
+are archived with this field specified as zero. 
 
 The @code{mtime} field is the data modification time of the file at
 the time it was archived.  It is the ASCII representation of the octal