[banshee] README.releasing: add note about updating copyrights

[Andrés Aragoneses <aaragoneses src gnome org>]

commit 44f57cc23327615c20dfe5e6774c33f8813ac7e5
Author: Andrés G. Aragoneses <knocte gmail com>
Date:   Tue Mar 18 16:58:25 2014 +0100

    README.releasing: add note about updating copyrights

 extras/README.releasing |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/extras/README.releasing b/extras/README.releasing
index 6dfcec5..bcad28f 100644
--- a/extras/README.releasing
+++ b/extras/README.releasing
@@ -10,6 +10,10 @@ https://wiki.gnome.org/Apps/Banshee/StableReleasesPolicy
   (if the previous release was 2.9.0)
 * Update AUTHORS (cd extras/ && ./create-authors > ../AUTHORS)
 * Update NEWS
+* Update copyright years if needed, in the following paths:
+  + src/Core/Banshee.ThickClient/Banshee.Gui.Dialogs/AboutDialog.cs
+  + src/AssemblyInfo.cs.in
+  + COPYING
 * Check version in configure.ac (don't forget the display version)
 * Update banshee.doap, build/windows/Installer*
 * Run `make distcheck`