added postgresql support to Java cookbook

cr https://cr.amazon.com/r/2564271/
Bump default passenger version to the latest bugfix release 4.0.46.

cr https://cr.amazon.com/r/2649697/
Enable Java apps without a DB backend again.

Set local vars in case of no database type given.
Merge branch 'master-chef-11.4' into mainline-chef-11.4