Skip upgrade if letsencrypt is upgrading its certificates

src/freedombone-upgrade

 # clear temporary files
 rm -rf /tmp/*
 
+# Is letsencrypt updating its certificates?
+# If yes then skip the upgrade to avoid any collisions
+if [ -f ~/temp_renewletsencrypt.txt ]; then
+    exit 0
+fi
+
 UTILS_FILES="/usr/share/${PROJECT_NAME}/utils/${PROJECT_NAME}-utils-*"
 for f in $UTILS_FILES
 do