maintaining.texi: Suopport fo Arch has been moved to obolte.

Remove references that imply otherwise.

doc/emacs/ChangeLog

+2014-12-08  Eric S. Raymond  <esr@snark.thyrsus.com>
+
+	* maintaining.texi: Suopport fo Arch has been moved to obolte,
+	remove references that imply otherwise.
+
 2014-11-29  Paul Eggert  <eggert@cs.ucla.edu>
 
 	Lessen focus on ChangeLog files, as opposed to change log entries.

doc/emacs/maintaining.texi

@@ -31,11 +31,11 @@ versions of a source file, storing information such as the creation
 time of each version, who made it, and a description of what was
 changed.
 
-  The Emacs version control interface is called @dfn{VC}@.  VC commands
-work with several different version control systems; currently, it
-supports GNU Arch, Bazaar, CVS, Git, Mercurial, Monotone, RCS,
+  The Emacs version control interface is called @dfn{VC}@.  VC
+commands work with several different version control systems;
+currently, it supports Bazaar, CVS, Git, Mercurial, Monotone, RCS,
 SCCS/CSSC, and Subversion.  Of these, the GNU project distributes CVS,
-Arch, RCS, and Bazaar.
+RCS, and Bazaar.
 
   VC is enabled automatically whenever you visit a file governed by a
 version control system.  To disable VC entirely, set the customizable
@@ -163,14 +163,6 @@ similar to CVS but without its problems (e.g., it supports atomic
 commits of filesets, and versioning of directories, symbolic links,
 meta-data, renames, copies, and deletes).
 
-@cindex GNU Arch
-@cindex Arch
-@item
-GNU Arch is one of the earliest @dfn{decentralized} version control
-systems (the other being Monotone).  @xref{VCS Concepts}, for a
-description of decentralized version control systems.  It is no longer
-under active development, and has been deprecated in favor of Bazaar.
-
 @cindex git
 @item
 Git is a decentralized version control system originally invented by
@@ -280,8 +272,8 @@ number and severity of conflicts that actually occur.
   SCCS always uses locking.  RCS is lock-based by default but can be
 told to operate in a merging style.  CVS and Subversion are
 merge-based by default but can be told to operate in a locking mode.
-Decentralized version control systems, such as GNU Arch, Git, and
-Mercurial, are exclusively merging-based.
+Decentralized version control systems, such as Git and Mercurial, are
+exclusively merging-based.
 
   VC mode supports both locking and merging version control.  The
 terms ``commit'' and ``update'' are used in newer version control