fix insertMany overload

was faulty before

source/mongoschema/db.d

@@ -609,7 +609,7 @@ mixin template MongoSchema()
 	}
 
 	/// Inserts many documents at once. The resulting IDs of the symbols will be generated by the server and not known to the caller.
-	static void insertMany(T)(T documents, InsertFlags options = InsertFlags.none)
+	static void insertMany(T)(T documents, InsertManyOptions options = InsertManyOptions.init)
 			if (isInputRange!T && is(ElementType!T : typeof(this)))
 	{
 		import std.array : array;