Merge pull request #103 from armandsar/master

Support laravel 5.6

Author: Shawn McCool

composer.json

@@ -16,7 +16,7 @@
  "require": {
  "backup-manager/backup-manager": "^1.0",
  "php": ">=5.5.0",
- "symfony/process": "^2.0||^3.0",
+ "symfony/process": "^2.0||^3.0||^4.0",
  "illuminate/support": "^4.0||^5.0",
  "illuminate/container": "^4.0||^5.0",
  "illuminate/console": "^4.0||^5.0"