add function cporig

cporig makes a copy of a file $FILENAME and names ist $FILENAME.orig

functions.sh

@@ -996,5 +996,11 @@ convert_to_subvolume () {
     set +x
     return 0
 
+}
+
+cporig () {
+
+    cp -b -i "${1}" "${1}.orig"
+
 }
 #EOF