Add Mike Ounsworth to acknowledgements

For #278

Author: davidben

draft-ietf-plants-merkle-tree-certs.md

@@ -2460,7 +2460,7 @@ assert h.hexdigest() == '7fd9c8b926e9d2b5cf831560e8ce295a5ef97ad5c5ede4ea0dea28a
 
 This document stands on the shoulders of giants and builds upon decades of work in TLS authentication, X.509, and Certificate Transparency. The authors would like to thank all those who have contributed over the history of these protocols.
 
-The authors additionally thank Bob Beck, Corey Bonnell, Ryan Dickson, Aaron Gable, Nick Harper, Jacob Hoffman-Andrews, Russ Housley, Dennis Jackson, Ilari Liusvaara, Sanketh Menda, Matt Mueller, Chris Patton, Michael Richardson, Ryan Sleevi, and Emily Stark for many valuable discussions and insights which led to this document, as well as feedback and contributions to the document itself. We wish to thank Mia Celeste in particular, whose implementation of an earlier draft revealed several pitfalls.
+The authors additionally thank Bob Beck, Corey Bonnell, Ryan Dickson, Aaron Gable, Nick Harper, Jacob Hoffman-Andrews, Russ Housley, Dennis Jackson, Ilari Liusvaara, Sanketh Menda, Matt Mueller, Mike Ounsworth, Chris Patton, Michael Richardson, Ryan Sleevi, and Emily Stark for many valuable discussions and insights which led to this document, as well as feedback and contributions to the document itself. We wish to thank Mia Celeste in particular, whose implementation of an earlier draft revealed several pitfalls.
 
 The idea to mint tree heads infrequently was originally described by Richard Barnes in {{STH-Discipline}}. The size optimization in Merkle Tree Certificates is an application of this idea to the certificate itself.