The idea is that xml-roundtrip should *never* be expected from a
XmlPullParser. So what we need is a method that parses the content of an
element without relying on getText() returning text if on START_TAG or
END_TAG. This is already done by PubSubs ItemProvider.
Also add PacketParserUtils.parseElement() which will return the current
element as String and use this method in PubSub's ItemProvider.
instead of using the old baseName=smack appendix=project.name approach,
we are now going convention over configuration and renaming the
subprojects directories to the proper name.
Having a prefix is actually very helpful, because the resulting
libraries will be named like the subproject. And a core-4.0.0-rc1.jar is
not as explicit about what it actually *is* as a
smack-core-4.0.0-rc1.jar.
SMACK-265
