title: How to automate the updating of AMI images in AWS?
body: <p>I've created an AWS AMI image in which have all my required applications installed in it.Later on I used autoscaling to create ec2 instances from the AMI image (in which I created before).
  what I need to do is:
  Updating the codes inside the AMI image,so the instances will use the new version.and this happens often, 
  I know that I can create a new image every time, but is there anyway to automate this process? for instance, updating it directly from git, or jenkins or .... 
  How can I possibility automate this process?</p>