Bump to version v0.21.0

Author: Polpetta

config/config.tex

@@ -14,7 +14,7 @@
 \newcommand{\myLocation}{Padova}                                % dove
 \newcommand{\myAA}{2016-2017}                                   % anno
 \newcommand{\myCopyright}{CC-BY-SA-4.0}                         % copyright
-\newcommand{\myVersion}{v0.20.0}                                % versione
+\newcommand{\myVersion}{v0.21.0}                                % versione
 \newcommand{\myRelease}{
 https://github.com/Polpetta/SecurityAndRiskManagementNotes}
 \newcommand{\myIssue}{