QmlDesigner.DocumentManager: Support component property of Tab

Change-Id: Iaf2d1160904023db3c66c6e536c5cf812a71e3fb
Reviewed-by: Marco Bubke <marco.bubke@digia.com>
ProjectTreeView: Find all nodes

Change-Id: I5c28c7f05b8e4766a5e04e00d9c8cd7e48b8cd95
Reviewed-by: Eike Ziller <eike.ziller@digia.com>