Add Qt 5.4.0 changelog for QtAndroidExtras

Change-Id: I5e5d1869d0a04f8e190181949bc1975de7c03938
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>

dist/changes-5.4.0

+Qt 5.4 introduces many new features and improvements as well as bugfixes
+over the 5.3.x series. For more details, refer to the online documentation
+included in this distribution. The documentation is also available online:
+
+  http://qt-project.org/doc/qt-5.4
+
+The Qt version 5.4 series is binary compatible with the 5.3.x series.
+Applications compiled for 5.3 will continue to run with 5.4.
+
+Some of the changes listed in this file include issue tracking numbers
+corresponding to tasks in the Qt Bug Tracker:
+
+  http://bugreports.qt-project.org/
+
+Each of these identifiers can be entered in the bug tracker to obtain more
+information about a particular change.
+
+****************************************************************************
+*                          Library                                         *
+****************************************************************************
+
+QtAndroidExtras
+-------------
+
+ - Notification example icon and documentation updated.
+ - QAndroidJniObject class documentation fixed.