Update README.md
Update README.md
Working version
Output progression properly
Download file from S3
Handle several clients that can be setup in config file. Each client have their own SQS channel.

TODO:
Communicate back through SQS:
  - workflowID
  - progression
  - statuses and errors

PErform JSON input validation
handle all input parameters (many are ignored for now)
Improve overall decider by adding DeciderBrain.php
Handles Decider events properly, can be extended at will to handle all possible events
Still need to send a Deicision task once one transcoding job is over, for now I am wiating for Amazon team to reply to my question: https://forums.aws.amazon.com/thread.jspa?threadID=145914&tstart=0
Fixed a couple of typos