Add changelog for 5.3.1

Change-Id: I5d9c67a2f89c0c191de9e6de24d068fca17dba0e
Reviewed-by: Jani Heikkinen <jani.heikkinen@digia.com>

dist/changes-5.3.1

+Qt 5.3.1 is a bug-fix release. It maintains both forward and backward
+compatibility (source and binary) with Qt 5.3.0.
+
+For more details, refer to the online documentation included in this
+distribution. The documentation is also available online:
+
+  http://qt-project.org/doc/qt-5.3
+
+The Qt version 5.3 series is binary compatible with the 5.2.x series.
+Applications compiled for 5.2 will continue to run with 5.3.
+
+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                                         *
+****************************************************************************
+
+
+QtQuick
+-------
+
+ - Platform Specific Changes:
+   * Added canPaste property to TextInput element also on platforms that
+     don't support a clipboard (QT_NO_CLIPBOARD is defined).
+