Add release notes page for version 26.0.0

Change-Id: I0973b24dd006b8a96ddd2c11302e9b79ca7c4876
diff --git a/releasenotes/source/v26.0.0.rst b/releasenotes/source/v26.0.0.rst
new file mode 100644
index 0000000..4161f89
--- /dev/null
+++ b/releasenotes/source/v26.0.0.rst
@@ -0,0 +1,5 @@
+=====================
+v26.0.0 Release Notes
+=====================
+.. release-notes:: 26.0.0 Release Notes
+   :version: 26.0.0