look into error_chain

[cyphar]

This is basically a reboot of the snafu porting effort. I will need to consider this for a bit longer, but I like that error-chain has a much more opaque-to-the-user API -- all that's exposed is ErrorKind. Also the foreign_links feature composes much better than snafu. But I'll need to think about this a lot more (and probably create some test examples).

[HadrienG2]

Just in case you haven't seen this blog post pass by, here's a nice overview/comparison of the various available Rust error handling crates.