record official releases that follow a certain structure, with public access via https://isabelle.sketis.net/repos/isabelle/raw-file/tip/Admin/Release/official (NB: Isabelle2013-1 had to be retracted);
--- a/Admin/Release/CHECKLIST Thu Mar 25 08:52:15 2021 +0000
+++ b/Admin/Release/CHECKLIST Sat Mar 27 15:56:49 2021 +0100
@@ -94,4 +94,6 @@
Post-release
============
+- update Admin/Release/official
+
- update /home/isabelle and /home/isabelle/html-data
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Admin/Release/official Sat Mar 27 15:56:49 2021 +0100
@@ -0,0 +1,11 @@
+Isabelle2021
+Isabelle2020
+Isabelle2019
+Isabelle2018
+Isabelle2017
+Isabelle2016-1
+Isabelle2016
+Isabelle2015
+Isabelle2014
+Isabelle2013-2
+Isabelle2013