[goptlib/master] Note master→main name change in ChangeLog.

[dcf at torproject.org]

commit e6425ce5287c9545e5ce00b356156b57b4edbcd8
Author: David Fifield <david at bamsoftware.com>
Date:   Sat May 29 01:01:20 2021 -0600

    Note master→main name change in ChangeLog.
---
 ChangeLog | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 2aae857..12391ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+The default and development branch is now "main" rather than "master".
+The master branch will no longer be updated.
+https://lists.torproject.org/pipermail/anti-censorship-team/2021-May/000168.html
+If you have an existing clone of the master branch, run these commands
+to update it:
+	git fetch origin
+	git remote set-head origin -a
+	git branch --move master main
+	git branch --set-upstream-to=origin/main main
+
 == v1.1.0
 
 Added the Log function.