Add cornerRadius property

GMStepper/GMStepper/Base.lproj/Main.storyboard

@@ -31,6 +31,9 @@
                                     <userDefinedRuntimeAttribute type="number" keyPath="maximumValue">
                                         <integer key="value" value="9"/>
                                     </userDefinedRuntimeAttribute>
+                                    <userDefinedRuntimeAttribute type="number" keyPath="cornerRadius">
+                                        <real key="value" value="4"/>
+                                    </userDefinedRuntimeAttribute>
                                 </userDefinedRuntimeAttributes>
                             </view>
                         </subviews>

GMStepper/GMStepper/GMStepper.swift

@@ -86,6 +86,13 @@ import UIKit
         }
     }
     
+    @IBInspectable public var cornerRadius: CGFloat = 4.0 {
+        didSet {
+            layer.cornerRadius = cornerRadius
+            clipsToBounds = true
+        }
+    }
+    
     private let leftButton = UIButton()
     private let rightButton = UIButton()
     private let label = UILabel()
@@ -121,6 +128,9 @@ import UIKit
         label.backgroundColor = labelBackgroundColor
         label.font = labelFont
         addSubview(label)
+        
+        layer.cornerRadius = cornerRadius
+        clipsToBounds = true
     }
     
     public override func layoutSubviews() {