title: How to add min and max limit for Thikness property in WPF control?
body: <p>I want to create custom control with few dependency properties. </p>
  
  <p>Those properties of Thikness return type.</p>
  
  <p>My control will be used by designers in Blend.</p>
  
  <p>In Blend some Thikness properties are limited. 
  For example BorderThickness cannot be less than 0. </p>
  
  <p>How to create thinkness property with min value 1 and max 3? (Blend should validate data in same way like BorderThickness - user input doesnot allowed) </p>