Move formatBanner to metro-core

Reviewed By: rafeca

Differential Revision: D6555773

fbshipit-source-id: 9d10a3d03c88eeaa2d6845518da3dacab8b556b0

Author: Peter van der Zee

local-cli/server/checkNodeVersion.js

@@ -9,7 +9,7 @@
 'use strict';
 
 var chalk = require('chalk');
-var formatBanner = require('metro/src/lib/formatBanner');
+var formatBanner = require('metro-core/src/formatBanner');
 var semver = require('semver');
 
 module.exports = function() {