Create a parent POM for librairies dependency management.
Some librairies (commons-io, http-components, commons-lang, jena, jean-arq, spring-core...) are used by various services or portlets. The problem is that without a common way to define dependencies versions we have a lot of incoherences...
For instance, some are using Jena 2.6.1 while other (and helpers) are relying on 2.6.4. The fact is that it may have side effect. (Between 2.6.1 and 2.6.4, the whole ARQ was removed from Jena for instance)