Improve deployability of Maven artifacts to public repository.
Although IRF hosts its own Maven repository, the Openfire release artifacts should be available on a central Maven repository (we should use our own repo only for -SNAPSHOT artifacts).
Various IRF projects are published to the central repository using Sonatypes OSS sync, which is described here: http://central.sonatype.org/pages/ossrh-guide.html
Sonatype applies some strict requirements to projects being published this way, some of which are currently not met by the Openfire project. This should be improved upon, to allow for easy deployment of Openfire artifacts.