Bug fixes, API improvements, and decoupled input methods

3.3.0.0

• Added debug rendering to show destination rects, offsets, etc.
• Fixed bug when clearing entity's children and it didn't update.
• Fixed SpaceBefore property on first item in container.
• Fixed bug with tabs panel buttons and scaling.
• Added new anchor type: AutoInlineNoBreak.
• API improvements (note: may break old code).
• Fixed exception with select list update (out of range).
• Fixed BringToFront with inherit parent properties setting.
• Added SendToBack() function.
• Changed PopulateDict into ToEntitiesDictionary().
• Changed some public functions to be internal / protected.
• Renamed IsInsideEntity() to IsTouching().
• Added MouseInput provider interface, allowing the user to implement alternative mouse-based input methods (like touch).
• Added KeyboardInput provider interface, allowing the user to implement alternative keyboard-based input methods.
• Fixed global scaling with percent-based sizes that grow / shrink too much.