[VOL-5545] Update voltha docs

- release notes for VOLTHA versions 2.6 to 2.15 with new Jira links and adjust release schedule details
- update old links
- remove ONF references and links
- update e-mail links
- update copright notices

Change-Id: Id6be18986a8f52f2dfcc07e2b0d2efcb0ae1c0e4
Signed-off-by: serkant.uluderya <serkant.uluderya@netsia.com>
diff --git a/_templates/meta_refresh.html b/_templates/meta_refresh.html
index fde0998..e7d24fb 100644
--- a/_templates/meta_refresh.html
+++ b/_templates/meta_refresh.html
@@ -1,5 +1,5 @@
 <!--
-SPDX-FileCopyrightText: 2020-2023 Open Networking Foundation (ONF) and the ONF Contributors
+SPDX-FileCopyrightText: 2020-2023 Linux Foundation Broadband Contributors
 
 SPDX-License-Identifier: Apache-2.0
 --!>