fix Libraries/Components/Touchable lint warnings

Summary: fix 4 lint warnings under Libraries/Components/Touchable directory
Closes https://github.com/facebook/react-native/pull/4449

Reviewed By: svcscm

Differential Revision: D2705537

Pulled By: spicyj

fb-gh-sync-id: 0c573d846a2263819c2a0bffe0a178eee1fe3fca

Libraries/Components/Touchable/BoundingDimensions.js

@@ -2,7 +2,7 @@
  * @providesModule BoundingDimensions
  */
 
-"use strict";
+'use strict';
 
 var PooledClass = require('PooledClass');
 

Libraries/Components/Touchable/Position.js

@@ -2,7 +2,7 @@
  * @providesModule Position
  */
 
-"use strict";
+'use strict';
 
 var PooledClass = require('PooledClass');
 

Libraries/Components/Touchable/Touchable.js

@@ -426,12 +426,12 @@ var TouchableMixin = {
         top: PRESS_EXPAND_PX,
         bottom: PRESS_EXPAND_PX
       };
-      
+
     var pressExpandLeft = pressRectOffset.left;
     var pressExpandTop = pressRectOffset.top;
     var pressExpandRight = pressRectOffset.right;
     var pressExpandBottom = pressRectOffset.bottom;
-    
+
     var touch = TouchEventUtils.extractSingleTouch(e.nativeEvent);
     var pageX = touch && touch.pageX;
     var pageY = touch && touch.pageY;