[configuration] Change Commons-Configuration getVector to getSet?

Hi all,

I am looking at a chunk of code like this:
 Vector packages = Turbine.getConfiguration()
                    .getVector(TurbineConstants.MODULE_PACKAGES);

                ObjectUtils.addOnce(packages,
                        GenericLoader.getBasePackage());

from Layout Loader...

And it seems to me that commons-configuration getVector should be deprecated
in favor of getSet().  I can't think why you would want duplicate values, so
getSet() makes more sense then getList().

Then, funky call's like the ObjectUtils.addOnce() wouldn't be needed...

Opinons?  And do we have to deprecate getVector() since we haven't released
from sandbox yet?

Eric Pugh