Add 2.3.1 changelog stub
Add 2.3.1 changelog stub

ThiefMaster/indico,DirkHoffmann/indico,DirkHoffmann/indico,indico/indico,indico/indico,pferreir/indico,indico/indico,ThiefMaster/indico,pferreir/indico,ThiefMaster/indico,DirkHoffmann/indico,DirkHoffmann/indico,indico/indico,ThiefMaster/indico,pferreir/indico,pferreir/indico