Added CHANGES entry for #6316.

CHANGES

@@ -1,4 +1,5 @@
 [1.9.13]
+- [BREAKING CHANGE] TexturePacker writes using a new format (TextureAtlas can still read old format). See #6316.
 - GWT: Key codes set with Gdx.input.setCatchKey prevent default browser behaviour
 - Added Scaling.contain mode: Scales the source to fit the target while keeping the same aspect ratio, but the source is not scaled at all if smaller in both directions.
 - API Addition: Added hasContents() to Clipboard interface, to reduce clipboard notifications on iOS 14
@@ -7,6 +8,7 @@
   Following changes might be done depending on platform: Keys.STAR to Keys.NUMPAD_MULTIPLY, Keys.SLASH to Keys.NUMPAD_DIVIDE, Keys.NUM to Keys.NUM_LOCK, Keys.COMMA to Keys.NUMPAD_COMMA, Keys.PERIOD to Keys.NUMPAD_DOT, Keys.COMMA to Keys.NUMPAD_COMMA, Keys.ENTER to Keys.NUMPAD_ENTER, Keys.PLUS to Keys.NUMPAD_ADD, Keys.MINUS to Keys.NUMPAD_SUBTRACT
 - Added a QuadFloatTree class.
 - Desktop: Cubemap Seamless feature is now enabled by default when supported, can be changed via backend specific methods, see supportsCubeMapSeamless and enableCubeMapSeamless in both LwjglGraphics and Lwjgl3Graphics.
+- API Addition: TextureAtlas reads arbitrary name/value pairs for each region. See #6316.
 
 [1.9.12]
 - [BREAKING CHANGE] iOS: Changed how Retina/hdpi handled on iOS. See #3709.