Elaborate on this library's capabilities & link to GPT Function calli…

…ng in a nutshell video

README.md

@@ -8,7 +8,7 @@ OpenAI APIs for XP
 [![Supports PHP 8.0+](https://raw.githubusercontent.com/xp-framework/web/master/static/php-8_0plus.svg)](http://php.net/)
 [![Latest Stable Version](https://poser.pugx.org/xp-forge/openai/version.svg)](https://packagist.org/packages/xp-forge/openai)
 
-This library implements OpenAI APIs with a low-level abstraction approach.
+This library implements OpenAI APIs with a low-level abstraction approach, supporting their REST and realtime APIs, request and response streaming, function calling and TikToken encoding.
 
 Completions
 -----------
@@ -344,4 +344,5 @@ See also
 * https://github.com/openai/tiktoken/
 * https://github.com/openai/openai-python
 * https://github.com/openai/openai-node
-* https://github.com/Azure-Samples/azure-openai-reverse-proxy
+* https://github.com/Azure-Samples/azure-openai-reverse-proxy
+* https://www.youtube.com/watch?v=i-oHvHejdsc - GPT Function calling in a nutshell