Add release notes for 1.10.3-cs4

Signed-off-by: Brian Goff <[email protected]>

cs-engine/release-notes/prior-release-notes.md

@@ -12,6 +12,11 @@ Docker Engine release notes. It includes issues, fixes, and new features.
 
 Refer to the [detailed list](https://github.com/docker/docker/releases) of all changes since the release of CS Engine 1.10.3-cs3
 
+## CS Engine 1.10.3-cs4
+(12 Jan 2017)
+
+Bumps RunC version to address CVE-2016-9962.
+
 ## CS Engine 1.10.3-cs3
 (25 April 2016)
 
@@ -332,4 +337,4 @@ Because this addition is preventative, no CVE-ID is requested.
 (23 Apr 2015)
 
 First release, see the [Docker Engine 1.6.0 Release notes](/v1.6/release-notes/)
-  for more details.
+  for more details.