Fix dependencies to include Laravel 5.5

Author: mikebronner

README.md

@@ -24,7 +24,7 @@ relationships. This package is the attempt to address those requirements.
 
 ## Requirements
 -   PHP >= 7.1.3
--   Laravel >=5.5.0
+-   Laravel >= 5.5
 
 ## Installation
 ```

composer.json

@@ -9,8 +9,8 @@
         }
     ],
     "require": {
-        "illuminate/cache": "5.6.*",
-        "illuminate/database": "5.6.*",
+        "illuminate/cache": "5.5 - 5.6",
+        "illuminate/database": "5.5 - 5.6",
         "php": ">=7.1.3"
     },
     "require-dev": {