Replace error_chain with ThisError

[urschrei]

Greatly expand defined errors, and remove all ad-hoc error messages

• [x] I agree to follow the project's code of conduct.

• [ ] I added an entry to CHANGELOG.md if knowledge of this change could be valuable to users.

[lnicola]

Looks fine, though to be honest in a library like this I'd prefer a hand-rolled error enum. They're not that much harder to write and build times are much lower unless you're already using proc macros.

[urschrei]

I suppose so although we have some crates in the georust ecosystem using thiserror, so there's a reasonable chance it's already in the tree.

[urschrei]

(Not geo or geo-types, though. Not yet)

[michaelkirk]

LGTM!

[urschrei]

bors r+

[bors[bot]]

Build succeeded:

• ci result