If an roster push with a roster entry without any group is processed,
then the entry is not updated, because unfiledEntries.contains(entry)
would return true, as the RosterEntry.equals() method only compares the
name.
We simply fix it by always removing the entry first and then adding it
again.
Thanks to Christian Schudt for pointing this out.
SMACK-559
Removed some throw declarations from methods, so some try/catch blocks
could be removed.
Use switch/case instead of if/else if.
Make members final when possible.
Add logger statements in case of error IQ result and remove superfluous
check of instanceof IQ.
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
