[transform] add perspective property to transform

Summary:
![matrixflip](https://cloud.githubusercontent.com/assets/1509831/8701143/607b069c-2b10-11e5-9c54-8b9767e74e16.gif)

cc @sahrens @vjeux
Closes https://github.com/facebook/react-native/pull/1980
Github Author: chirag04 <jain_chirag04@yahoo.com>

Libraries/StyleSheet/TransformPropTypes.js

@@ -16,6 +16,7 @@ var ReactPropTypes = require('ReactPropTypes');
 var TransformPropTypes = {
   transform: ReactPropTypes.arrayOf(
     ReactPropTypes.oneOfType([
+      ReactPropTypes.shape({perspective: ReactPropTypes.number}),
       ReactPropTypes.shape({rotate: ReactPropTypes.string}),
       ReactPropTypes.shape({rotateX: ReactPropTypes.string}),
       ReactPropTypes.shape({rotateY: ReactPropTypes.string}),

Libraries/StyleSheet/precomputeStyle.js

@@ -58,6 +58,9 @@ function _precomputeTransforms(style: Object): Object {
       case 'matrix':
         MatrixMath.multiplyInto(result, result, value);
         break;
+      case 'perspective':
+        _multiplyTransform(result, MatrixMath.reusePerspectiveCommand, [value]);
+        break;
       case 'rotateX':
         _multiplyTransform(result, MatrixMath.reuseRotateXCommand, [_convertToRadians(value)]);
         break;

Libraries/Utilities/MatrixMath.js

@@ -65,6 +65,10 @@ var MatrixMath = {
     matrixCommand[10] = z;
   },
 
+  reusePerspectiveCommand: function(matrixCommand, p) {
+    matrixCommand[11] = -1 / p;
+  },
+
   reuseScaleXCommand(matrixCommand, factor) {
     matrixCommand[0] = factor;
   },