Improve documentation on starting up grid (#1268)

* add Swarm full grid setup

* Remove /wd/hub endpoint reference

Author: luisfcorreia

README.md

@@ -36,12 +36,14 @@ $ docker run -d -p 4444:4444 -p 7900:7900 --shm-size 2g selenium/standalone-fire
 $ docker run -d -p 4444:4444 -p 7900:7900 -v /dev/shm:/dev/shm selenium/standalone-firefox:4.0.0-beta-3-prerelease-20210422
 ```
 
-2. Point your WebDriver tests to http://localhost:4444/wd/hub
+2. Point your WebDriver tests to http://localhost:4444 *
 
 3. That's it! 
 
 4. (Optional) To see what is happening inside the container, head to http://localhost:7900 (password is `secret`).
 
+* Grid 3 used "/wd/hub", while it should also work, it is no longer required
+
 More details about visualising the container activity, check the [Debugging](#debugging) section.
 
 :point_up: When executing `docker run` for an image that contains a browser please either mount 

docker-compose-v3-full-grid-swarm.yml

@@ -0,0 +1,62 @@
+# To start Docker in Swarm mode, you need to run `docker swarm init`
+# To deploy the Grid, `docker stack deploy -c docker-compose-v3-swarm.yml grid`
+# Stop with `docker stack rm grid`
+# Stop swarm mode `docker swarm leave --force`
+
+version: '3.7'
+
+services:
+  chrome:
+    image: selenium/node-chrome:4.0.0-beta-3-prerelease-20210422
+    volumes:
+      - /dev/shm:/dev/shm
+    environment:
+      - SE_EVENT_BUS_HOST=selenium-hub
+      - SE_EVENT_BUS_PUBLISH_PORT=4442
+      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
+    deploy:
+      replicas: 1
+    entrypoint: bash -c 'SE_OPTS="--host $$HOSTNAME" /opt/bin/entry_point.sh'
+
+  edge:
+    image: selenium/node-edge:4.0.0-beta-3-prerelease-20210422
+    volumes:
+      - /dev/shm:/dev/shm
+    environment:
+      - SE_EVENT_BUS_HOST=selenium-hub
+      - SE_EVENT_BUS_PUBLISH_PORT=4442
+      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
+    deploy:
+      replicas: 1
+    entrypoint: bash -c 'SE_OPTS="--host $$HOSTNAME" /opt/bin/entry_point.sh'
+
+  firefox:
+    image: selenium/node-firefox:4.0.0-beta-3-prerelease-20210422
+    volumes:
+      - /dev/shm:/dev/shm
+    environment:
+      - SE_EVENT_BUS_HOST=selenium-hub
+      - SE_EVENT_BUS_PUBLISH_PORT=4442
+      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
+    deploy:
+      replicas: 1
+    entrypoint: bash -c 'SE_OPTS="--host $$HOSTNAME" /opt/bin/entry_point.sh'
+
+  opera:
+    image: selenium/node-opera:4.0.0-beta-3-prerelease-20210422
+    volumes:
+      - /dev/shm:/dev/shm
+    environment:
+      - SE_EVENT_BUS_HOST=selenium-hub
+      - SE_EVENT_BUS_PUBLISH_PORT=4442
+      - SE_EVENT_BUS_SUBSCRIBE_PORT=4443
+    deploy:
+      replicas: 1
+    entrypoint: bash -c 'SE_OPTS="--host $$HOSTNAME" /opt/bin/entry_point.sh'
+
+  selenium-hub:
+    image: selenium/hub:4.0.0-beta-3-prerelease-20210422
+    ports:
+      - "4442:4442"
+      - "4443:4443"
+      - "4444:4444"