Clarify deprecation

Author: msciotti

README.md

@@ -1,6 +1,10 @@
 # Discord RPC
 
-> This library has been deprecated in favor of Discord's GameSDK. [Learn more here](https://discordapp.com/developers/docs/game-sdk/sdk-starter-guide)
+## Deprecation Notice
+
+This library has been deprecated in favor of Discord's GameSDK. [Learn more here](https://discordapp.com/developers/docs/game-sdk/sdk-starter-guide)
+
+---
 
 This is a library for interfacing your game with a locally running Discord desktop client. It's known to work on Windows, macOS, and Linux. You can use the lib directly if you like, or use it as a guide to writing your own if it doesn't suit your game as is. PRs/feedback welcome if you have an improvement everyone might want, or can describe how this doesn't meet your needs.