Add support for clamping for NativeAnimated on iOS

Summary:
This diff adds support for clamping on iOS. It separates out code originally submitted in #9048.

Test plan (required)

Run UIExplorer NativeAnimated examples before and after - compare the results. Pay special attention to the new clamped spring example.
Closes https://github.com/facebook/react-native/pull/9625

Differential Revision: D4053231

fbshipit-source-id: 29048de444ff5f6d7fe7dce7897399b483ee6d2d

Examples/UIExplorer/js/NativeAnimationsExample.js

@@ -320,7 +320,7 @@ exports.examples = [
     },
   },
   {
-    title: 'Scale interpolation',
+    title: 'Scale interpolation with clamping',
     description: 'description',
     render: function() {
       return (
@@ -335,8 +335,9 @@ exports.examples = [
                   transform: [
                     {
                       scale: anim.interpolate({
-                        inputRange: [0, 1],
+                        inputRange: [0, 0.5],
                         outputRange: [1, 1.4],
+                        extrapolateRight: 'clamp',
                       })
                     }
                   ],