Stringer for ErrClass and ErrCode ?

[slyphon]

The functionality might already exist somewhere, but it seems like it'd be useful for error reporting to make a stringer for ErrClass and ErrCode to return human-readable names for the corresponding constants.

It'd mean that go generate would have to be run when the relevant constants were changed, but it seems like this should be relatively easy to do.

Would you accept a pull request that set this up?

[lhchavez]

there's precedent for that (e.g. #523) so PR away!

now that you mention it, it may be worth adding an Action to check whether all the go generated files are up to date. that we can do separately.