Added ReadMe for docker

ReadMe.txt

+Install Docker:
+https://www.docker.com/products/docker-desktop
+
+Have Docker running - either open the application or in terminal (docker start)
+
+docker ps -> check running containers
+docker ps -a -> check all containers
+
+Go into the main folder of this project
+Execute - docker-compose up -d --build (This calls the docker-compose.yaml file and starts the containers.
+The build option is for the Dockerfile - it enables the mysqli extension for the database);
+
+To check if the containers are running - docker ps
+
+Visit -> http://localhost:8000
+
+To stop the containers - docker-compose down