v1.7.0: Multi-selection update

WARNING: The following changes may affect your project if you're updating from an older version:

• DraggedReferenceSourceUI component's Object Reference variable is changed to Object[] References
• Moved "Can Drop Parent On Child" and "Can Add Objects To Pseudo Scenes" properties from HierarchyDragDropListener to RuntimeHierarchy
• hierarchy.Select(someTransform) function's equivalent is now hierarchy.Select(someTransform, RuntimeHierarchy.SelectOptions.FocusOnSelection)
• RuntimeHierarchy's "Create Dragged References On Hold" property is changed to "Pointer Long Press Action"

Release Notes:

• Added "Multi Selection" option to RuntimeHierarchy:
  • SelectionChangedDelegate now takes ReadOnlyCollection<Transform> parameter
  • CurrentSelection returns ReadOnlyCollection<Transform>
  • Select function has a variant that takes IList<Transform>
  • Deselect function has variants that allow deselecting only a subset of the selection
  • Added IsSelected function to check if a Transform is selected
• Added tooltip support to RuntimeHierarchy (when enabled, hovering the cursor over a Transform for a while will display its name in a tooltip)
• Added bool IsLocked property to RuntimeInspector and RuntimeHierarchy which prevents changing the inspected/selected object from outside (similar to Unity's own Inspector lock)
• Space between expand arrow and the label next to it is now configurable via UISkin
• Expand arrows now scale correctly with UISkin's Line Height