Added support for laravel 6

Author: JaskirtPooni

composer.json

@@ -10,13 +10,13 @@
         }
     ],
     "require": {
-        "php": ">=7.0",
-        "illuminate/support": "^5.4",
-        "illuminate/database": "^5.4",
-        "illuminate/validation": "^5.4"
+        "php": ">=7.2",
+        "illuminate/support": "^6.0",
+        "illuminate/database": "^6.0",
+        "illuminate/validation": "^6.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^6.0",
+        "phpunit/phpunit": "^6.0 || ^7.0 ||^8.0",
         "mockery/mockery": "^0.9.9",
         "squizlabs/php_codesniffer": "^2.8",
         "satooshi/php-coveralls": "^1.0"