Bump support to Laravel 6

Author: jasonmccreary

composer.json

@@ -9,12 +9,12 @@
     "license": "MIT",
     "require": {
         "symfony/yaml": "^4.3",
-        "illuminate/console": "^5.8",
-        "illuminate/filesystem": "^5.8",
-        "illuminate/support": "^5.8"
+        "illuminate/console": "^6.0",
+        "illuminate/filesystem": "^6.0",
+        "illuminate/support": "^6.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7.5",
+        "phpunit/phpunit": "^8.0",
         "mockery/mockery": "^1.2"
     },
     "autoload": {