Updated the changelog for 1.5.12 (#6634)

Author: meln1k

changelog.md

@@ -1,4 +1,4 @@
-## Changes from 1.5.11 to 1.5.12 (unreleased)
+## Changes from 1.5.11 to 1.5.12
 
 ### Default for "kill_retry_timeout" was increased to 30 seconds
 
@@ -35,9 +35,16 @@ Additionally, we have added support for Debian Stretch.
 
 ### Fixed Issues
 
-- [MARATHON-7568](https://jira.mesosphere.com/browse/MARATHON-7568) - We now redact any Zookeeper credentials from the /v2/info response endpoint.
+- [MARATHON-7568](https://jira.mesosphere.com/browse/MARATHON-7568) We now redact any Zookeeper credentials from the /v2/info response endpoint.
+- [MARATHON-8413](https://jira.mesosphere.com/browse/MARATHON-8413) Fixed a bug where versions feature did not work if Marathon was launched using Java 9.
+- [MARATHON-8095](https://jira.mesosphere.com/browse/MARATHON-8095) Fixed a bug where proxying the PATCH call was impossible due to Java limitations.
+- [MARATHON-8430](https://jira.mesosphere.com/browse/MARATHON-8430) Readiness checks now work with self-signed certificates.
 - Updated version of [Marathon UI to 1.3.1](https://github.com/mesosphere/marathon-ui/blob/master/CHANGELOG.md#131---2018-06-07):
-    - [MARATHON-8255](https://jira.mesosphere.com/browse/MARATHON-8255) - Marathon UI properly shows fetch URLs in the edit dialog, now.
+    - [MARATHON-8255](https://jira.mesosphere.com/browse/MARATHON-8255) Marathon UI properly shows fetch URLs in the edit dialog, now.
+- [MARATHON-7941](https://jira.mesosphere.com/browse/MARATHON-7941) Default for unreachable strategy on PUT /apps now matches POST requests.
+- [MARATHON-8084](https://jira.mesosphere.com/browse/MARATHON-8084) Fix issue in which `POST /v2/apps/{app_id}/restart` would not proxy properly.
+- [MARATHON-7390](https://jira.mesosphere.com/browse/MARATHON-7390) Fix issue in which Marathon would become unresponsive for a long time if Zookeeper DNS cannot be resolved at launch.
+- Fixed a data migration issue in which UNIQUE constraint value was stripped when empty.
 
 ## Changes from 1.5.10 to 1.5.11