Add license check by file to build

* composer require --dev malukenho/docheader
* Add license layout
* Add check license to the build

.docheader

@@ -0,0 +1,8 @@
+/*
+ * This file is part of Respect/Validation.
+ *
+ * (c) Alexandre Gomes Gaigalas <alexandre@gaigalas.net>
+ *
+ * For the full copyright and license information, please view the "LICENSE.md"
+ * file that was distributed with this source code.
+ */

.travis.yml

@@ -16,6 +16,7 @@ before_script:
 
 script:
   - vendor/bin/phpunit --configuration phpunit.xml.dist --colors --coverage-clover=coverage.clover
+  - vendor/bin/docheader check library tests
 
 after_script:
   - test "5.6" == "${TRAVIS_PHP_VERSION}" && wget https://scrutinizer-ci.com/ocular.phar

composer.json

@@ -21,7 +21,8 @@
         "mikey179/vfsStream": "^1.5",
         "phpunit/phpunit": "~5.3",
         "symfony/validator": "~2.6.9",
-        "zendframework/zend-validator": "~2.3"
+        "zendframework/zend-validator": "~2.3",
+        "malukenho/docheader": "^0.1.4"
     },
     "suggest": {
         "ext-bcmath": "Arbitrary Precision Mathematics",