Intrusive Ptr + a buffer pool.
Started with the code from: http://alsharabi.blogspot.nl/2009/06/boostintrusiveptr-is-one-of-six-smart.html
and morphed it into a RAII style grabage collecting buffer pool.
QueuePtr is distributed under the BSD 3-Clause License. See the
LICENSE file at the project root for the full text. Each source
file carries an SPDX-License-Identifier: BSD-3-Clause tag.