Update notes for submitted changes

* Fix Xamarin bug 8271 (buggy Screen.FromRectangle)
Update notes for submitted changes

* Fix FWNX-909 (and Xamarin 8907)
Update notes for submitted changes

* Fix crash from null control in ContainerControl
Update notes for submitted changes

* Improve output if Xinerama isn't installed (FWNX-1046)
Update notes for submitted changes

* Fix Timer deadlock problem (cherrypick)
Update notes for submitted changes

* Fix icon in unity launcher (FWNX-892)