Update composer

Author: gdarko

composer.json

@@ -1,22 +1,30 @@
 {
-    "name": "ignitekit/wp-orm",
-    "description": "Laravel Eloquent inspired ORM package for WordPress",
-    "keywords": ["wordpress", "plugin", "orm", "eloquent", "sql"],
-    "homepage": "https://github.com/ignitekit/wp-orm",
-    "require": {
-        "illuminate/database": "^5.4",
-        "illuminate/pagination": "^5.4"
-    },
-    "license": "GPL-2.0",
-    "authors": [
-        {
-            "name": "Darko Gjorgjijoski",
-            "email": "dg@darkog.com"
-        }
-    ],
-    "autoload" : {
-      "psr-4" : {
-        "IgniteKit\\WP\\ORM\\": "src/"
-      }
+  "name": "ignitekit/wp-orm",
+  "description": "Laravel Eloquent inspired ORM package for WordPress",
+  "keywords": [
+    "wordpress",
+    "plugin",
+    "orm",
+    "eloquent",
+    "sql"
+  ],
+  "homepage": "https://github.com/ignitekit/wp-orm",
+  "require": {
+    "php": "^5.6.4|^7.0",
+    "ext-json": "*",
+    "illuminate/database": "^5.4",
+    "illuminate/pagination": "^5.4"
+  },
+  "license": "GPL-2.0",
+  "authors": [
+    {
+      "name": "Darko Gjorgjijoski",
+      "email": "dg@darkog.com"
     }
+  ],
+  "autoload": {
+    "psr-4": {
+      "IgniteKit\\WP\\ORM\\": "src/"
+    }
+  }
 }