docs: Update README

Signed-off-by: Alexander Kurbatov <sir.alkurbatov@yandex.ru>

Author: alkurbatov

README.md

@@ -2,14 +2,19 @@
 Dockerized StarCraft 2 Linux application.
 
 ## Usage
+1. Pull the latest image:
 ```bash
-# Build the image:
-$ docker build -t docker-sc2 .
+$ docker pull alkurbatov/sc2
+```
 
-# Run the image:
-$ docker run -p 8167:8167 docker-sc2
+2. Run the image:
+```
+$ docker run -p 8167:8167 alkurbatov/sc2
 ```
 
+3. Connect to the game
+Example code for the C++ API can be found [here](https://github.com/cpp-sc2/scrubber).
+
 ## License
 Copyright (c) 2021-2022 Alexander Kurbatov