🎈 6.12.0: bumped minor and updated changelog (gazebosim#1682)

* bumped minor and updated changelog

Signed-off-by: Dharini Dutia <dharini@openrobotics.org>

* fixed changelog as per feedback and updated migration guide

Signed-off-by: Dharini Dutia <dharini@openrobotics.org>

Signed-off-by: Dharini Dutia <dharini@openrobotics.org>
Signed-off-by: Silvio <silvio@traversaro.it>

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.10.2 FATAL_ERROR)
 #============================================================================
 # Initialize the project
 #============================================================================
-project(ignition-gazebo6 VERSION 6.11.0)
+project(ignition-gazebo6 VERSION 6.12.0)
 set (GZ_DISTRIBUTION "Fortress")
 
 #============================================================================

Changelog.md

@@ -1,5 +1,19 @@
 ## Ignition Gazebo 6.x
 
+### Gazebo Sim 6.12.0 (2022-08-30)
+
+1. Add topic parameter to thrust plugin
+    * [Pull request #1681](https://github.com/gazebosim/gz-sim/pull/1681)
+
+1. Add information about `<topic>` system parameter
+    * [Pull request #1671](https://github.com/gazebosim/gz-sim/pull/1671)
+
+1. Adding tests for hydrodynamics
+    * [Pull request #1617](https://github.com/gazebosim/gz-sim/pull/1617)
+
+1. Fix Windows and Doxygen
+    * [Pull request #1643](https://github.com/gazebosim/gz-sim/pull/1643)
+
 ### Gazebo Sim 6.11.0 (2022-08-17)
 
 1. Add support for specifying log record period

Migration.md

@@ -5,6 +5,12 @@ Deprecated code produces compile-time warnings. These warning serve as
 notification to users that their code should be upgraded. The next major
 release will remove the deprecated code.
 
+## Ignition Gazebo 6.11.X to 6.12.X
+
+ * **Modified**:
+   + In the Hydrodynamics plugin, inverted the added mass contribution to make it
+     act in the correct direction.
+
 ## Ignition Gazebo 6.1 to 6.2
 
 * If no `<namespace>` is given to the `Thruster` plugin, the namespace now