move to maven central

[jimkont]

the aksw maven repo is down a lot and would be good to deploy all our artifacts to maven central.

We did the same for aksw. The procedure has a few steps but the first one is to request the hosting.
To do so, everyone who wants to be able to deploy, create an account..
@kurzum maybe you can set responsibilities

We then request rights for org.nlp2rdf in a new ticket like the following
https://issues.sonatype.org/browse/OSSRH-17378

A complete guide can be found here: http://central.sonatype.org/pages/producers.html#individual-projects-open-source-software-repository-hosting-ossrh

[jimkont]

I will set everything up but people who want to make releases should have deploy rights