RangeSlider V2.3

I Improved RangeSlider mouse pressed handling. Now all mouse events work with stack panel. This leads to more comfortable work when ```IsMoveToPointEnable = True```. 
User dont need now to aim at thin buttons, you can press in any place of container. For ex, range slider height = 20, buttons height = 3. Now you can press mouse in any place of that 20 pixels and slider will change it`s position.

Behavior now excatly the same as in MS slider.