Add changes-5.1.1 file.

Task-number: QTBUG-32808
Change-Id: I998548df399ec6d2dd6b061b5ba2c1ca451276bc
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>

dist/changes-5.1.1

+Qt 5.1.1 is a bug-fix release. It maintains both forward and backward
+compatibility (source and binary) with Qt 5.1.0.
+
+For more details, refer to the online documentation included in this
+distribution. The documentation is also available online:
+
+  http://qt-project.org/doc/qt-5.1/
+
+The Qt version 5.1 series is binary compatible with the 5.0.x series.
+Applications compiled for 5.0 will continue to run with 5.1.
+
+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.
+
+****************************************************************************
+*                      Platform Specific Changes                           *
+****************************************************************************
+
+Qt for Windows
+--------------
+
+ - Use correct default audio output and input devices on Windows.
+ - [QTBUG-29206] DirectShow: avoid unnecessary RGB32 -> BGR32 conversion.
+ - [QTBUG-32282] DirectShow: Don't create the widget and renderer controls
+    until requested.
+ - [QTBUG-23822] Fix resource leak in directshow plugin.
+ - WMF: fixed MediaPlayer buffering logic.
+
+Qt for Android
+--------------
+
+ - Fixed potential memory leak when destroying a media player.
+ - Fixed media player showing black frames on some hardware.
+ - [QTBUG-31422] Make it possible for the media player to play assets.
+ - Fixed Java exception being thrown at app startup when using multimedia.
+
+Qt for BlackBerry
+-----------------
+
+ - [QTBUG-31534] Fix frame size of video playback.