fixed; display empty docs as {} in log output

schemas with _id and id set to false were output as undefined
instead of {}

follow up to #953

lib/document.js

@@ -1476,9 +1476,10 @@ Document.prototype.toJSON = function (options) {
  */
 
 Document.prototype.inspect = function (options) {
-  var opts = options && 'Object' == options.constructor.name
-    ? options
-    : undefined
+  var opts = options && 'Object' == options.constructor.name ? options :
+      this.schema.options.toObject ? clone(this.schema.options.toObject) :
+      {};
+  opts.minimize = false;
   return inspect(this.toObject(opts));
 };