Return non-zero exit code from wrong-react-native

Summary:
When used in automation, `wrong-react-native` can cause problems because it does not
report the issue via exit code.
Closes https://github.com/facebook/react-native/pull/5114

Reviewed By: svcscm

Differential Revision: D2799995

Pulled By: frantic

fb-gh-sync-id: 23c32dac9b0fcdbeaf48b94e9cb220c6c1b344aa

local-cli/wrong-react-native.js

@@ -15,3 +15,5 @@ console.error([
   'npm uninstall -g react-native',
   'npm install -g react-native-cli'
 ].join('\n'));
+
+process.exit(1);