Use thiserror for implementing custom error types

[ngutech21]

Instead of implementing the From-trait manually, I would recommend using thiserror crate https://docs.rs/thiserror/latest/thiserror/
This would get rid of most of the boilerplate code in the error types.

[thesimplekid]

Initially I did this to avoid a dependency, however I think you're right that using thiserror makes sense to avoid the boilerplate. So I will change this.

[thesimplekid]

Complete in:

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