Update to use maven-publishing plugin

I have the needed changes locally, but applying needs to wait for changes to the upload auth plugin to work with the new publishing scheme

this new plugin has a serious issue, if there is non Authentication defined in the settings.xml (basically <servers><server></server></servers>) then NPE will be thrown, see http://pastebin.com/YdPDZey3

the problem is SettingsXmlCredentialsProvider (line 70)