rename 'nativeConstraints' to 'layoutConstraints' for API consistency

Source/Constraint.swift

@@ -58,7 +58,7 @@ public class Constraint {
     public func updatePriorityMedium() -> Void { fatalError("Must be implemented by Concrete subclass.") }
     public func updatePriorityLow() -> Void { fatalError("Must be implemented by Concrete subclass.") }
 
-    public func nativeConstraints() -> [LayoutConstraint] { fatalError("Must be implemented by Concrete subclass.") }
+    public var layoutConstraints: [LayoutConstraint] { fatalError("Must be implemented by Concrete subclass.") }
     
     internal var makerFile: String = "Unknown"
     internal var makerLine: UInt = 0
@@ -199,7 +199,7 @@ internal class ConcreteConstraint: Constraint {
     
     private var installInfo: ConcreteConstraintInstallInfo? = nil
     
-    internal override func nativeConstraints() -> [LayoutConstraint] {
+    override var layoutConstraints: [LayoutConstraint] {
         if installInfo == nil {
             install()
         }

Tests/Tests.swift

@@ -302,10 +302,10 @@ class SnapKitTests: XCTestCase {
         var sizeNativeConstraints: [LayoutConstraint]!
         view.snp_makeConstraints { (make) -> Void in
             let topConstraint = make.top.equalToSuperview().inset(10).constraint
-            topNativeConstraints = topConstraint.nativeConstraints()
-            topNativeConstraint = topConstraint.nativeConstraints().first
+            topNativeConstraints = topConstraint.layoutConstraints
+            topNativeConstraint = topConstraint.layoutConstraints.first
             let sizeConstraints = make.size.equalTo(50).constraint
-            sizeNativeConstraints = sizeConstraints.nativeConstraints()
+            sizeNativeConstraints = sizeConstraints.layoutConstraints
         }
 
         XCTAssertEqual(topNativeConstraints.count, 1, "make.top should creates one native constraint")