[GTK] use GtkInterop for all Interops
[GTK] add missing window icon support
[WPF] Error when using nested TextEntry in Notebook sample in ScrollView.
[GTK] fix default icon size
[WPF] center all lines in wrapped centered labels
[Samples] exit application when main window is closed
[Samples] add sample for ellipsized label
[Samples] add sample for multiline text entry
Add cursor position and selection support to TextEntry

* add properties for cursor position and selection bounds
* add SelectedText property (which is writeble to support direct selection changes)
* add SelectionChanged event
* includes ComboBoxTextEntry support

WPF and GTK support is included. Mac has to be added.
Add text selection to samples
Initial suppport for multi-toolkit image support

Image objects loaded using a toolkit can now be used in
other toolkits.
Add public method for creating multi-resolution images
Offset dirtyRect in Canvas OnDraw to allow for CanvasBackend origin
Improve support for cross-toolkit images

Allow specifying an image loader callback. Secondary toolkits will use it to
load images on demand.
Fix NRE
Merge pull request #337 from hwthomas/master

[Gtk CanvasBackend]  Offset dirtyRect in Canvas OnDraw to allow for CanvasBackend origin
Merge pull request #335 from sevoku/samples

Samples additions
Merge pull request #334 from sevoku/add-text-cursor-selection

Add text cursor selection
Merge pull request #333 from sevoku/wpf-centered-label-fix

[WPF] center all lines in wrapped centered labels
Merge pull request #331 from sevoku/gtk-fixes

[Gtk] various fixes (interops, icons)