Blog about JDK 9 vs JDK 8 speed, taking modules into account

We need to know the perf impact of JDK 9, so we can advice our customers and consultants correctly.

Create a new blog article about JDK 8 vs JDK 9 performance for optaplanner-website, similar to this one:
https://www.optaplanner.org/blog/2014/03/20/HowMuchFasterIsJava8.html
Notice how it explains the methodology, raw results and then gives an opinion.
Tip: Copy paste the adoc file of that article, see this directory: https://github.com/kiegroup/optaplanner-website/tree/master/blog

Some things to take into account:

• Add yourself in users.yml in optaplanner-website
• JDK 9 defaults to Garbage collector G1, which is a lot slower on throughput (but better on latency).
  • Read and probably reference this: https://www.optaplanner.org/blog/2015/07/31/WhatIsTheFastestGarbageCollectorInJava8.html
  • Try both JDK 9 with the default GC and the GC that was default in JDK 8.
• If possible, also try both with module-info.java (in all used kie, drools, optaplanner and optaplanner-examples artifacts)
  • Compare it to without. Does it make a difference today? Yes/no, that's interesting info.
    • Clearly note that most perf improvements from module info are coming in future versions of JDK
  • You can maybe reuse the code from PLANNER-883