add `docker exec` command to readme

README.md

@@ -31,6 +31,7 @@ curl https://ollama.ai/install.sh | sh
 
 ```
 docker run -d -v ollama:/root/.ollama -p 11434:11434 --name ollama ollama/ollama
+docker exec -it ollama ollama run llama2
 ```
 
 For GPU support, use `--gpus=all`. See the Docker [image](https://hub.docker.com/r/ollama/ollama) for more information.