BUG-632: Fix NIO package thinko

It turns out we cannot just proxy around the Selector and
SelectorProvider -- we have to have our own. This is okay, as we can
nicely drop this in.

Change-Id: Idcda5b263bc584fbd9157f0d0fc57d4af82d08d4
Signed-off-by: Robert Varga <rovarga@cisco.com>