Minor optimization tweaks:

 - Update Netty to version 4.0.16.
 - Use the native Epoll transport if available.
 - Register the Jackson Afterburner module to speedup the marshaling to json.
Minor tweaks:

 - Update library versions in the README
 - Add more aggressive JVM options
 - Add missing file to the source_code listing
enable "SO_REUSEADDR"
update netty to 4.0.17
Integrate changes made by @normanmaurer:
"use proper config for PooledByteBufAllocator"
<https://github.com/normanmaurer/FrameworkBenchmarks/commit/411209c5d6248c981e21fea1479efdd1bbf6dade>
Merge pull request #805 from lneves/master

Minor optimization tweaks: