Fix the transform.rb to include dea_next log aggregator property

With the most updated cf-release and follow the instruction of bosh-lite.

"bosh deploy" will result:

Preparing configuration
  binding configuration: Error filling in template `dea_logging_agent.json.erb' for `dea_next/0' (line 3: Can't find property `["loggregator.trafficcontroller"]') (00:00:02).

The problem is the script/transform.rb delete all the properties in dea_next job (only has loggregator.trafficcontroller property from cf-aws-template.yml.erb). The fix will make the "bosh deploy" going through.

-Shaozhen