Add the dotnet binding info.

[AsakusaRinne]

Hi, SciSharp STACK has made a C#/.NET Binding of llama.cpp, named LLamaSharp. May I kindly ask if it can be added to readme to let more dotnet users know it?

Currently it has provided the following features:

1. Basic APIs, including getting the embeddings, tokenization and detokenization, loading and inferring the model, etc.
2. Chat session, providing easy-to-use APIs to make a chat bot.
3. Quantization, providing an API to quantize the model in C#.
4. Integration of ASP.NET core, making it easy to deploy the chat service.
5. One-click installation, without compiling llama.cpp or other manipulations.

SciSharp STACK developers will maintain it and follow up llama.cpp. I believe we can make this .NET Binding better with the great works of llama.cpp! :)