added PHP_CodeSniffer example

refs #6

source https://github.com/squizlabs/PHP_CodeSniffer/wiki/Reporting#printing-a-checkstyle-report

Author: staabm

README.md

@@ -31,27 +31,39 @@ vendor/bin/cs2pr /path/to/checkstyle-report.xml
 
 ## Pipe the output of another commmand
 
+... works for __any__ command which produces a checkstyle-formatted report.
+
+Examples can bee seen below:
+
 ### Using [PHPStan](https://github.com/phpstan/phpstan)
+
 ```bash
 phpstan analyse --error-format=checkstyle | vendor/bin/cs2pr
 ```
 
 ### Using [Psalm](https://github.com/vimeo/psalm)
+
 ```bash
 psalm --output-format=checkstyle | vendor/bin/cs2pr
 ```
 
 _Psalm even supports the required format natively, therefore you might even use this instead:_
+
 ```bash
 psalm --output-format=github
 ```
 
 ### Using [PHP Coding Standards Fixer](https://github.com/FriendsOfPHP/PHP-CS-Fixer)
+
 ```bash
 php-cs-fixer --format=checkstyle | vendor/bin/cs2pr
 ```
 
-... works for __any__ command which produces a checkstyle-formatted report.
+### Using [PHP_CodeSniffer](https://github.com/squizlabs/PHP_CodeSniffer)
+
+```bash
+phpcs --report=checkstyle /path/to/code | vendor/bin/cs2pr
+```
 
 ## phpunit support?