Add SIP user with the adduser command

src/freedombone-adduser

     echo "$MY_USERNAME added as a blog user"
 fi
 
+if grep -q "install_sip" $COMPLETION_FILE; then
+    freedombone-addsipuser -u $MY_USERNAME -e $SIP_EXTENSION -p "$NEW_USER_PASSWORD"
+    if [ ! "$?" = "0" ]; then
+        echo 'SIP user could not be added'
+        userdel -r $MY_USERNAME
+        exit 10
+    fi
+fi
+
 clear
 echo "New user $MY_USERNAME was created"
 echo "Their login password is $NEW_USER_PASSWORD"