Update Marlin.ino config info

Marlin/Marlin.ino

-/*
-================================================================================
+/*==============================================================================
 
   Marlin Firmware
 
 Greetings! Thank you for choosing Marlin 2 as your 3D printer firmware.
 
 To configure Marlin you must edit Configuration.h and Configuration_adv.h
-located in the root 'Marlin' folder. Check the config/examples folder to see if
-there's a more suitable starting-point for your specific hardware.
+located in the root 'Marlin' folder. Check our Configurations repository to
+see if there's a more suitable starting-point for your specific hardware.
 
 Before diving in, we recommend the following essential links:
 
 
 Configuration
 
+  - https://github.com/MarlinFirmware/Configurations
+    Example configurations for several printer models.
+
   - https://www.youtube.com/watch?v=3gwWVFtdg-4
     A good 20-minute overview of Marlin configuration by Tom Sanladerer.
     (Applies to Marlin 1.0.x, so Jerk and Acceleration should be halved.)
 
   - https://marlinfw.org/docs/development/coding_standards.html
     Before submitting code get to know the Coding Standards.
-*/
+
+
+------------------------------------------------------------------------------*/