[unity] Moved unity changelog entry to new "Breaking Changes" section.

CHANGELOG.md

@@ -181,6 +181,10 @@
   * `TrackEntry` has an additional field called `holdPrevious`. It can be used to counter act a limitation of `AnimationState` resulting in "dipping" of parts of the animation. For a full discussion of the problem and the solution we've implemented, see this [forum thread](http://esotericsoftware.com/forum/Probably-Easy-Animation-mixing-with-multiple-tracks-10682?p=48130&hilit=holdprevious#p48130).
 
 ### Unity
+
+* **Breaking Changes**
+  * **Removed PoseSkeleton() and PoseWithAnimation()** extension methods to prevent issues where animations are not mixed out. Problem was that these methods did not set AnimationState, leaving incorrect state at e.g. attachments enabled at slots when starting subsequent animations. As a replacement you can use `AnimationState.ClearTrack(0);` followed by `var entry = AnimationState.SetAnimation(0, animation, loop); entry.TrackTime = time` to achieve similar behaviour.
+
 * **Runtime and Editor, and Assembly Definition** Files and folders have been reorganized into "Runtime" and "Editor". Each of these have an `.asmdef` file that defines these separately as their own assembly in Unity. For projects not using assembly definition, you may delete the `.asmdef` files. These assembly definitions will be ignored by older versions of Unity that don't support it.
 	* In this scheme, the entirety of the base spine-csharp runtime is inside the "Runtime" folder, to be compiled in the same assembly as spine-unity so they can continue to share internal members.
 * **SkeletonAnimator is now SkeletonMecanim** The Spine-Unity Mecanim-driven component `SkeletonAnimator` has been renamed `SkeletonMecanim` to make it more autocomplete-friendly and more obvious at human-glance. The .meta files and guids should remain intact so existing projects and prefabs should not break. However, user code needs to be updated to use `SkeletonMecanim`.
@@ -222,7 +226,6 @@
     * `CompareFunction.LessEqual` for `Mask Interaction - Visible Inside Mask`
     * `CompareFunction.Greater` for `Mask Interaction - Visible Outside Mask`
 * **RectMask2D Support for SkeletonGraphic** Both `SkeletonGraphic` shaders '`Spine/SkeletonGraphic`' and '`Spine/SkeletonGraphic Tint Black`' now respect masking areas defined via Unity's `RectMask2D` component.
-* **Removed PoseSkeleton() and PoseWithAnimation()** extension methods to prevent issues where animations are not mixed out. Problem was that these methods did not set AnimationState, leaving incorrect state at e.g. attachments enabled at slots when starting subsequent animations. As a replacement you can use `AnimationState.ClearTrack(0);` followed by `var entry = AnimationState.SetAnimation(0, animation, loop); entry.TrackTime = time` to achieve similar behaviour.
 * **Spine Preferences stored in Assets/Editor/SpineSettings.asset** Now Spine uses the new `SettingsProvider` API, storing settings in a SpineSettings.asset file which can be shared with team members. Your old preferences are automatically migrated to the new system.
 
 ### XNA/MonoGame