Feature Request: S-expressions Import/Export Support

[jgarte]

I'd like to add s-expressions import/export support for the-way.

https://github.com/rotty/lexpr-rs

Related to #127

WDYT of this feature?

[Ninjani]

I was hoping to use a crate like serde-any to support a bunch of formats at once. It hasn't been updated in a while though and doesn't have s-expressions support. License is permissive though, could make a fork that adds more formats.

Also related to #127