adding myself to AUTHORS as per commits (#1109)

commits:
ff92365
5907cef

Author: stefanofiorentino

AUTHORS

@@ -97,6 +97,7 @@ selaselah <selah@outlook.com>
 Sergiy80 <sil2004@gmail.com>
 sergzub <sergzub@gmail.com>
 Stefan Schweter <stefan@schweter.it>
+Stefano Fiorentino <stefano.fiore84@gmail.com>
 Steffen Kieß <Steffen.Kiess@ipvs.uni-stuttgart.de>
 Steven Hahn <hahnse@ornl.gov>
 Stuart Eichert <stuart@fivemicro.com>