Fixing Issue #235 TreeView problem with overwriting selected values at Loaded event with default Items[0] value and not selecting TreeItem because Item was selected before TreeItem was because WPF is LazyLoading TreeItems for Items after Loaded event...
Added comments to code
Fixing Issue #263. Wpf.FrameBackend did not UpdateChildPlacement after setting new Content(child)
Removed part for delayed selecting of VisualItem because it should be solved more generally for all cases. So this pull now only contains fix for issue #235
[WPF] Add proper support for default foreground color in TextLayout

The underlying FormattedText object is now regenerated when the
foreground color is changed.
TreeView collapse events:

- events Collapsing and Collapsed
- implementation in GTK and WPF
- samples
Formatting
[Xwt] Fix Rectangle.Union wrt to empty surfaces.

A union of an empty rectangle and a non-empty one should yield the empty one. Previously the method could inject some junk 0 values for x or y in that case.
Revert "[Xwt] Fix Rectangle.Union wrt to empty surfaces."

This reverts commit 2146534f4d278d0bf0995efceb9ad3d962f75a8a.
This commit broke the iOS designer and also appears to be incorrect
mathematically. Union the zero point with a rect should give you a
resulting rect which includes the zero point.
[Xwt.Gtk] Handle when multiple drag/drop datatypes are allowed

If SetDragDropTarget is called and multiple types are passed in,
DragDataRequests will be set equal to the number of items passed
in.

Once we process all of those we need to emit the event. This is
done even if the drag operation did not contain any of the
supported transfer data types.

The exact case where this was failing was if you registered as supporting
Foo and Bar and then tried to do a drag of type Bar. On my system it
would check the 'Bar' TransferDataType' first and then not emit the
events because DragDataRequests was equal to 1. Then it woudl check
'Foo', which was not part of the drag and so there was no data, so
it would bail out before emitting.
Don't build gtk3 by default
Merge branch 'sevoku-gtk3'
Merge pull request #253 from DavidKarlas/Issue235

Fixing Issue #235
Merge pull request #265 from DavidKarlas/wpfFrameAlignment

Fixing Issue #263.
Merge pull request #342 from mono/fix-wpf-context-background

[WPF] Add proper support for default foreground color in TextLayout
Merge pull request #348 from residuum/master

[TreeView] [Gtk] [WPF] OnRowCollapsing and OnRowCollapsed implemented
[Mac] Implement RowCollapsed/RowCollapsing
Merge branch 'extend-webview' of git://github.com/sevoku/xwt into sevoku-extend-webview

Conflicts:
	Xwt.Gtk/Xwt.GtkBackend/GtkInterop.cs
Merge branch 'sevoku-extend-webview'
Merge remote-tracking branch 'mono/master' into fix-gtk-popover-backend

Conflicts:
	Xwt.Gtk/Xwt.GtkBackend/PopoverBackend.cs