RELICENSE: Piotr Trojanek grant (#2381)

RELICENSE/ptroja.md

+# Permission to Relicense under MPLv2 or any other OSI approved license chosen by the current ZeroMQ BDFL
+
+This is a statement by Piotr Trojanek that grants permission to relicense its
+copyrights in the libzmq C++ library (ZeroMQ) under the Mozilla Public License
+v2 (MPLv2) or any other Open Source Initiative approved license chosen by the
+current ZeroMQ BDFL (Benevolent Dictator for Life).
+
+A portion of the commits made by the Github handle "{{github username}}", with
+commit author "{{github commit author}}", are copyright of {{ name }} .
+This document hereby grants the libzmq project team to relicense libzmq,
+including all past, present and future contributions of the author listed above.
+
+Piotr Trojanek
+2017/03/19