Add CHANGES entry

4939.	[test]		Add basic unit tests for update_sigs(). [GL #135]

(cherry picked from commit 4885809e)
(cherry picked from commit 1f9b0cbc)
(cherry picked from commit d6b8bca3)
(cherry picked from commit 6338ca08)

CHANGES

+4939.	[test]		Add basic unit tests for update_sigs(). [GL #135]
+
 4933.	[bug]		Not creating signing keys for an inline signed zone
 			prevented changes applied to the raw zone from being
 			reflected in the secure zone until signing keys were