feat(tool): PHP Mess Detector (#23)

Author: yknsilva

README.md

@@ -90,6 +90,7 @@ phpctl sh echo 'Hello, World!' # To run arbitrary sh commands inside the contain
 |----------------|-------------------------------------------------------------------------------------------------------------------------------|
 | `phpunit`      | [PHPUnit](https://phpunit.de) is a programmer-oriented testing framework for PHP.                                             |
 | `php-cs-fixer` | [PHP Coding Standards Fixer (PHP CS Fixer)](https://cs.symfony.com/) fixes your code to follow standards.                     |
+| `phpmd`        | [PHP Mess Detector](https://phpmd.org/) looks for several potential problems within your source code.                         |
 | `phpstan`      | [PHPStan](https://phpstan.org/) finds bugs in your code without writing tests. It's open-source and free.                     |
 | `infection`    | [Infection](https://infection.github.io) is a Mutation Testing Framework.                                                     |
 | `pest`         | [Pest](https://pestphp.com) is a testing framework with a focus on simplicity.                                                |

bin/phpmd

@@ -0,0 +1,2 @@
+#!/usr/bin/env sh
+phpctl phpmd $@

examples/phpmd/.gitignore

@@ -0,0 +1 @@
+vendor/

examples/phpmd/README.md

@@ -0,0 +1,16 @@
+# PHP Mess Detector
+
+An example of [PHP Mess Detector](https://phpmd.org/) usage.
+
+Run `phpctl phpmd src text cleancode,controversial,design,naming,unusedcode` to get PHPMD output execution for [Example](./src/Example.php) class.
+
+You should have an output as following:
+```shell
+/usr/local/src/src/Example.php:6   LongVariable         Avoid excessively long variable names like $thiIsAnAmazingVariable. Keep variable name length under 20.
+/usr/local/src/src/Example.php:8   UnusedLocalVariable  Avoid unused local variables such as '$anotherVariable'.
+/usr/local/src/src/Example.php:11  CamelCaseMethodName  The method snake_case_method is not named in camelCase.
+/usr/local/src/src/Example.php:17  MissingImport        Missing class import via use statement (line '17', column '23').
+/usr/local/src/src/Example.php:18  EmptyCatchBlock      Avoid using empty try-catch blocks in uselessCatchBlock.
+/usr/local/src/src/Example.php:24  UndefinedVariable    Avoid using undefined variables such as '$age' which will lead to PHP notices.
+/usr/local/src/src/Example.php:24  UnusedLocalVariable  Avoid unused local variables such as '$age'.
+```

examples/phpmd/composer.json

@@ -0,0 +1,10 @@
+{
+    "autoload": {
+        "psr-4": {
+            "App\\": "src/"
+        }
+    },
+    "require-dev": {
+        "phpmd/phpmd": "^2.15"
+    }
+}