Convert domains to lowercase, persist current domain model on resolver

src/Database/Concerns/ConvertsDomainsToLowercase.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Stancl\Tenancy\Database\Concerns;
+
+trait ConvertsDomainsToLowercase
+{
+    public static function bootConvertsDomainsToLowercase()
+    {
+        static::saving(function ($model) {
+            $model->domain = strtolower($model->domain);
+        });
+    }
+}