Exit if prosody modules were not installed

src/freedombone-app-xmpp

@@ -812,6 +812,7 @@ function install_xmpp {
     update_prosody_modules initial
     if [ ! -d /var/lib/prosody/prosody-modules ]; then
         echo $'No prosody modules available'
+        exit 82634
     fi
 
     # create a certificate