Link LinkingIOS in SampleApp

Summary:
Closes https://github.com/facebook/react-native/pull/656
Github Author: jcgertig <jcgertig@gmail.com>

Test Plan: Imported from GitHub, without a `Test Plan:` line.

Libraries/LinkingIOS/RCTLinkingManager.h

@@ -13,6 +13,9 @@
 
 @interface RCTLinkingManager : NSObject <RCTBridgeModule>
 
-+ (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation;
++ (BOOL)application:(UIApplication *)application
+            openURL:(NSURL *)URL
+  sourceApplication:(NSString *)sourceApplication
+         annotation:(id)annotation;
 
 @end