(vc-default-backend, vc-path, vc-consult-headers):

(vc-default-backend, vc-path, vc-consult-headers):
(vc-mistrust-permissions, vc-keep-workfiles): Customization
variables, moved here from vc.el.
(vc-trunk-p, vc-minor-revision, vc-branch-part): Moved to vc.el.
(vc-backend): Renamed from vc-backend-deduce.  Callers changed.
(vc-match-substring, vc-lock-file, vc-parse-buffer, vc-master-info):
(vc-log-info, vc-consult-rcs-headers, vc-fetch-properties):
(vc-backend-subdirectory-name, vc-locking-user, vc-true-locking-user):
(vc-latest-version, vc-your-latest-version, vc-branch-version):
(vc-workfile-version): Functions moved here from vc.el.
(vc-log-info): Log program is no longer called through vc-do-command,
to avoid including the lengthy vc-do-command here.  It is done
directly through call-process now.  Removed obsolete parameter LAST.
(vc-status): Replaced by the much simpler version that gets the
information from the file properties.  Removed the obsolete
parameter vc-type.
(vc-parse-buffer): changed format of PATTERNS.  Each pattern is now a
list of 2 to 3 elements, the first being the pattern, the remaining
ones the numbers of subexpressions to refer to.
(vc-cvs-status): New per-file property, only used in the CVS case.
(vc-cvs-status): New function.
(vc-log-info): Adapted to new version of vc-parse-buffer
(vc-fetch-properties): Adapted to new version of vc-parse-buffer.
Better search regexp for CVS latest version.
(vc-log-info): Search for branch version only in the RCS case,
since this doesn't make sense for SCCS or CVS.
(vc-fetch-properties): CVS case: set vc-cvs-status.
(vc-locking-user): CVS case: use vc-cvs-status to determine if
the file is up-to-date, thus avoiding an expensive call to
vc-workfile-unchanged-p.
(vc-mode-line): Re-activated the code that makes the buffer read-only
if the work file is unchanged.  But the status of the work file
is now determined by looking at the already-computed mode string.