README.md in trackler-2.2.1.44

- old
+ new

@@ -16,50 +16,50 @@
 but they should be stripped before checking. All other non-digit characters
 are disallowed.
 
 ## Example 1: valid credit card number
 
-```
+```text
 4539 1488 0343 6467
 ```
 
 The first step of the Luhn algorithm is to double every second digit,
 starting from the right. We will be doubling
 
-```
+```text
 4_3_ 1_8_ 0_4_ 6_6_
 ```
 
 If doubling the number results in a number greater than 9 then subtract 9
 from the product. The results of our doubling:
 
-```
+```text
 8569 2478 0383 3437
 ```
 
 Then sum all of the digits:
 
-```
+```text
 8+5+6+9+2+4+7+8+0+3+8+3+3+4+3+7 = 80
 ```
 
 If the sum is evenly divisible by 10, then the number is valid. This number is valid!
 
 ## Example 2: invalid credit card number
 
-```
+```text
 8273 1232 7352 0569
 ```
 
 Double the second digits, starting from the right
 
-```
+```text
 7253 2262 5312 0539
 ```
 
 Sum the digits
 
-```
+```text
 7+2+5+3+2+2+6+2+5+3+1+2+0+5+3+9 = 57
 ```
 
 57 is not evenly divisible by 10, so this number is not valid.
 