[gimp/gimp-2-10] Issue #3990: make the status of the XCF docs a bit clearer (hopefully).

[Jehan <jehanp src gnome org>]

commit 8a400e304f646b678bc3378f0dd9c2ac7f7cf9bc
Author: Jehan <jehan girinstud io>
Date:   Fri Sep 27 01:01:31 2019 +0200

    Issue #3990: make the status of the XCF docs a bit clearer (hopefully).
    
    Though it may have started as an unofficial document, it is clearly now
    an official one (which should be obvious since it is in our source
    repository, but apparently some people get misled by the historical
    "Status" text to think this to be somehow unofficial).
    So first of all, change the s/official/unofficial/ mention.
    
    Secondly, add a small paragraph explicitly telling that the document is
    complete (and meant to be), to the best of our knowledge. This document
    is a detailed, full and exhaustive written "specification" of the XCF
    format up to GIMP 2.10.x (even though the normative spec is still the
    code itself). Now we are humans, we may have missed something, and if
    so, this is just to be considered as any other bug, and reported to us
    nicely to be fixed.
    
    (cherry picked from commit 80e2e0a50815cc643709ccbd7a7258b908ceac86)

 devel-docs/xcf.txt | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)
---
diff --git a/devel-docs/xcf.txt b/devel-docs/xcf.txt
index a54764b821..f68a99428f 100644
--- a/devel-docs/xcf.txt
+++ b/devel-docs/xcf.txt
@@ -20,7 +20,7 @@ License
 -------
 
 Copyright Henning Makholm <henning makholm net>, 2006-07-11
-Copyright various GIMP developers (see git log), 2009-2018
+Copyright various GIMP developers (see git log), 2009-2019
 
 This is free documentation; you can modify and/or redistribute
 it according to the terms of the GNU General Public License
@@ -124,16 +124,21 @@ https://web.archive.org/web/20161024115140/http://www.cinepaint.org/more/docs/xc
 Status
 ------
 
-This specification is an unofficial condensation and extrapolation of
-the XCF-writing and -reading code in version 2.10.0 of GIMP. Yet we
-remind that the ultimate reference is the loading and saving code of the
-XCF format.
+This specification is an official condensation and extrapolation of
+the XCF-writing and -reading code in version 2.10.14 of GIMP, and
+earlier versions. Yet we remind that the ultimate reference is the
+loading and saving code of the XCF format.
 
 Some of the normative statements made below are enforced by the XCF
 code in GIMP; others are just the authors' informed guess about
 "best practices" that would be likely to maximize interoperability
 with future versions of GIMP.
 
+This document is complete, relatively to GIMP 2.10 features stored in
+the XCF format, though if you discover any errors or missing features,
+we would be thankful if you could report it as a bug:
+https://gitlab.gnome.org/GNOME/gimp/issues
+
 
 Version history
 ---------------
@@ -170,6 +175,7 @@ Adds many layer modes, layer group masks, high-bit depth (precisions
 other than 8-bit gamma), zlib compression and 64-bit offsets for XCF
 files bigger than 4GB.
 
+
 1. BASIC CONCEPTS
 =================