Conditional Serde

Depend on Serialize and Deserialize only if the serde feature is activated.

Ever had to duplicate a full trait definition, just because you wanted some of its type members to conveniently implement Serialize and Deserialize depending on a feature? Worry no more, this crate provides the solution! Simply add a dependency to ConditionalSerde to your type member, and activate this crate's serde feature if yours is activated.