Package to fat jar.

[jiminhsieh]

It would much easier to benchmark without IntelliJ. We could benchmark in remote Linux server. Basically, I add 3 maven plugins - maven-jar-plugin, maven-assembly-plugin, and maven-shade-plugin. maven-jar-plugin and maven-assembly-plugin are used to package fat jar. maven-shade-plugin is used to deal that Akka-HTTP needs it to package reference.conf. It would generate jar with postfix - allInOne, otherwise Akka-HTTP couldn't work correctly.