[MOD-2318] iOS: Update Facebook iOS-SDK to 4.18.0, fix docs, add new methods

   var fb = require('facebook');
   
   var appID = '517802691665259';
   
   var win = Ti.UI.createWindow({
       backgroundColor: '#fff'
   });
    
   var btn = Ti.UI.createButton({
       title: 'Set App-ID and Access-Token'
   });
    
   btn.addEventListener('click', function() {
       fb.setAppID(appID);
       
       fb.setCurrentAccessToken({
           accessToken: 'my-new-token',
           permissions: ['email'],
           appID: appID,
           userID: 'hansknoechel'
       });
   });
    
   win.add(btn);
   win.open();