SWORDv2 Java client depends heavily on Apache Abdera, which is abandoned #5

As of May 2017, Apache Abdera has been abandoned: http://attic.apache.org/projects/abdera.html

However, it's used heavily by this JavaClient: https://github.com/swordapp/JavaClient2.0/blob/master/pom.xml#L164-L168

While I realize this project hasn't seen any maintenance updates in a long time, it'd be nice to move it to a different Java ATOM API (to avoid future security issues, etc). One example might be ROME: https://rometools.github.io/rome/

Without such an update, projects using SWORDv2 (like DSpace) may eventually need to move away from it, as maintaining an integration with abandoned dependencies becomes more and more difficult.