* doc/emacs/maintaining.texi (VCS Concepts): Make "revision" terminology
less CVS-specific.
(VC With A Merging VCS, VC With A Locking VCS): Add xref to
Registering node.
(Secondary VC Commands): Deleted. Promote subnodes.
(Log Buffer): Add command name for C-c C-c. Fix the name of the
log buffer. Add index entries.
(VCS Changesets, Types of Log File, VC With A Merging VCS): Use
"commit" terminology.
(Old Revisions): Move it to just before VC Change Log. "Tag" here
doesn't refer to tags tables. Note other possible forms of the
revision ID. C-x v = does not save.
(Registering): Note similarity to C-x v v action. Fix description
of how backends are chosen. De-document vc-default-init-revision.
(VC Change Log): Document C-x v l in VC-Dir buffer. Document RET
in root log buffers.
* lisp/vc/vc.el (vc-deduce-fileset): Minor doc fix.
* vc/vc.el (vc-revert-show-diff): New defcustom.
(vc-diff-internal): New arg specifying diff buffer.
(vc-revert): Obey vc-revert-show-diff. If we show a diff, don't
reuse an existing *vc-diff* buffer.
(vc-version-ediff, vc-ediff): New functions.
(vc-version-diff): Use vc-diff-build-argument-list-internal.
* doc/emacs/maintaining.texi (Old Revisions): Add paragraph on new function
vc-ediff.
* etc/NEWS: Document new function `vc-ediff'.
* lisp/vc/vc.el (vc-print-log-setup-buttons): Instead of using the
widget library for buttons, just use button.el.
* lisp/vc/log-view.el (log-view-mode-map): Don't inherit from
widget-keymap.
* lisp/vc/vc.el (vc-pull): Make vc-update an alias for this, instead of
the other way around.
* lisp/vc/vc-git.el (vc-git-branches, vc-git-pull)
(vc-git-merge-branch): New functions.
(vc-git-history): New var.
* lisp/vc/vc-hg.el (vc-hg-history): New var.
(vc-hg-pull): Perform default pull if called via Lisp by vc-pull.
(vc-hg-merge-branch): New function.
* vc/vc.el (vc-merge): Remove optional arg PROMPT. Always prompt
for a merge location.
* vc/vc-bzr.el (vc-bzr-pull): Remove unused var.
(vc-bzr-merge-branch): Always prompt.
(vc-bzr-async-command): Use the full branch filename.
* lisp/vc/vc-bzr.el (vc-bzr-admin-branchconf, vc-bzr-history): New vars.
(vc-bzr--branch-conf, vc-bzr-async-command, vc-bzr-pull)
(vc-bzr-merge-branch): New functions, implementing merge-branch
and pull operations.
* lisp/vc/vc.el (vc-merge): Use vc-BACKEND-merge-branch if available.
Accept optional prefix arg meaning to prompt for a command.
(vc-update): Use vc-BACKEND-pull if available. Accept optional
prefix arg meaning to prompt for a command.
(vc-pull): Alias for vc-update.
log-outgoing commands.
* lisp/vc/vc.el (vc-log-internal-common): Add a new argument and use it
to create a buffer local revert-buffer-function variable.
(vc-print-log-internal, vc-log-incoming, vc-log-outgoing): Pass a
revert-buffer-function lambda.
* vc/diff-mode.el (diff-vc-backend): New var.
* vc/vc.el (vc-deduce-backend): New fun. Handle diff buffers.
(vc-root-diff, vc-print-root-log, vc-log-incoming)
(vc-log-outgoing): Use it.
(vc-diff-internal): Set diff-vc-backend.
