; Move time-stamp release info from symbol-releases.eld to NEWS

Update the appropriate historical NEWS files with time-stamp feature
releases.  Suggested by Stefan Monnier.  All dates are from my notes.

* etc/symbol-releases.eld: Remove time-stamp,
reverting commit 69210eb84e of 17 March.
* etc/NEWS.19:
* etc/NEWS.20: Add 'time-stamp' feature paragraphs that
should have been written then.
* etc/NEWS.21: Add missing quotes, so symbol names can be identified.

etc/NEWS.19

@@ -2108,6 +2108,11 @@ mailabbrev.el used to have its own variable for this purpose
 ** In Buffer-Menu mode, the d and C-d commands (which mark buffers for
 deletion) now accept a prefix argument which serves as a repeat count.
 
+** 'time-stamp' can be disabled interactively with 'time-stamp-toggle-active'
+This new function works by toggling existing variable 'time-stamp-active'.
+When inactive, 'time-stamp' generates a warning message unless
+new variable 'time-stamp-warn-inactive' is nil.
+
 ** Changes in BibTeX mode.
 
 *** Reference keys can now be entered with TAB completion.  All
@@ -4982,6 +4987,12 @@ in a singleton list when it first inserts the prefix, but doesn't
 insert the prefix when processing events whose PLACE-SYMBOLs are
 already thus enclosed.
 
+** New function 'time-stamp' updates a template with the current time.
+This is intended to be used on 'write-file-hooks'.  The template details
+are controlled by file-local variables 'time-stamp-start', 'time-stamp-end',
+'time-stamp-line-limit', and 'time-stamp-format'.
+Disabled by turning off 'time-stamp-active'.
+
 
 
 * Changes in Emacs 19.15

etc/NEWS.20

@@ -925,6 +925,10 @@ reminder about upcoming diary entries.  See the documentation string
 for a sample shell script for calling this function automatically
 every night.
 
+** New convenience variable 'time-stamp-pattern'
+Using 'time-stamp-pattern', a file can specify several 'time-stamp'
+parameters with just one variable.
+
 ** Desktop changes
 
 *** All you need to do to enable use of the Desktop package, is to set

etc/NEWS.21

@@ -1488,13 +1488,13 @@ has the following new features:
 *** The patterns for finding the time stamp and for updating a pattern
 may match text spanning multiple lines.  For example, some people like
 to have the filename and date on separate lines.  The new variable
-time-stamp-inserts-lines controls the matching for multi-line patterns.
+'time-stamp-inserts-lines' controls the matching for multi-line patterns.
 
-*** More than one time stamp can be updated in the same file.  This
-feature is useful if you need separate time stamps in a program source
-file to both include in formatted documentation and insert in the
+*** More than one time stamp can be updated in the same file.
+This feature is useful if you need separate time stamps in a program
+source file to both include in formatted documentation and insert in the
 compiled binary.  The same time-stamp will be written at each matching
-pattern.  The variable time-stamp-count enables this new feature; it
+pattern.  The variable 'time-stamp-count' enables this new feature; it
 defaults to 1.
 
 ** Partial Completion mode now completes environment variables in

etc/symbol-releases.eld

@@ -50,8 +50,6 @@
  ("22.1" fun version<=)
  ("22.1" fun read-number)
  ("21.1" var text-property-default-nonsticky)
- ("20.3" var time-stamp-pattern)
- ("19.16" fun time-stamp)
 
 ;; Since much of early Emacs source history is lost, these versions are
 ;; conservative estimates: the actual version of first appearance may very