This program registers the current EC2 instance with the specified load balancer while the container is running. When the container exits, it unregisters the instance from the ELB.
Usage:
docker run -d -p 5000:5000 --name=webapp training/webapp
docker run -d \
-v /var/run/docker.sock:/var/run/docker.sock \
crewjam/dockerelb /dockerelb \
-container=webapp \
-elb=WebappLoadBalancer