Allow using custom builders on models

Use original model newEloquentBuilder to retrieve the builder used for a
model. This allows using custom builders on models, defining them with
UseEloquentBuilder attribute or $builder static property

Author: akyrey

src/Traits/ModelCaching.php

@@ -111,7 +111,7 @@ public function newEloquentBuilder($query)
         if (! $this->isCachable()) {
             $this->isCachable = false;
 
-            return new EloquentBuilder($query);
+            return parent::newEloquentBuilder($query);
         }
 
         return new CachedBuilder($query);