As of Undertow 1.3.0, several APIs have been changed: replacing Xnio's
Pool/Pooled references to Undertow's new ByteBufferPool abstraction.
This move has been made, as part of
https://issues.jboss.org/browse/UNDERTOW-522, to prepare deprecations in
the Xnio API.

This commit adds a new strategy to deal with both 1.0-1.2 and 1.3
Undertow generations.

Issue: SPR-13366