Add rate limiting for serialization

**Feature request**
It would be great to have serialization for parsers.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_serialization` with default `false`.

Start by locating the parser and configuration handling in the repository, since no file or test is named. Clarify whether the requested work is serialization or rate limiting, then define and test the behavior of an `enable_serialization` option whose default is `false`.

Written by the indexing model from the issue text.