Update breaking changes txt (behaviour change of JUCEApplicationBase::quit() on Android).

BREAKING-CHANGES.txt

@@ -63,6 +63,32 @@ Rationale
 The graph class was extremely old and creaky, and these changes is the start of
 an improvement process that should eventually result in it being broken down
 into fundamental graph building block classes for use in other contexts.
+
+
+Change
+------
+Calling JUCEApplicationBase::quit() on Android will now really quit the app,
+rather than just placing it in background. Starting with API level 21 (Android 5.0), the
+app will not appear in recent apps list after calling quit(). Prior to API 21, the app will still
+appear in recent app lists but when a user chooses the app, a new instance of the app will be started.
+
+
+Possible Issues
+---------------
+Any code calling JUCEApplicationBase::quit() to place the app in background will close the app instead.
+
+
+Workaround
+----------
+Use Process::hide().
+
+
+Rationale
+---------
+The old behaviour JUCEApplicationBase::quit() was confusing JUCE code, as a new instance of JUCE
+app was attempted to be created, while the older instance was still running in background. This
+would result in assertions when starting a second instance.
+
 
 
 Version 5.2.0