refactor: use subset of http-status

[snyamathi]

This PR addresses #26 by taking a subset of the status codes from http-status which contains a bunch of other unused entries which are contributing to bloat: https://unpkg.com/http-status@1.5.0/lib/index.js

This drops the total size of the package from 22.5 KiB to just 3.2 KiB without changing the message returned for each status code.

This would technically change the functionality if someone passed one of the non-numerical keys that are part of the http-status library, though it seems odd to have an error with e.statusCode = '401_CLASS' - it would become a 500 error after this change.

The documentation specifically calls out the status code as being a number so I'm not concerned about it. The docs even specify that the statusCode "Must be greater or equal 400" but I'm keeping the other error codes as well since it's hardly any weight and that very well could be a breaking change for some people.

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[lingyan]

This would technically change the functionality if someone passed one of the non-numerical keys that are part of the http-status library, though it seems odd to have an error with e.statusCode = '401_CLASS' - it would become a 500 error after this change.

Agree 401_CLASS is odd. For this kind of syntax, should we parse the status code from such string, instead of changing to 500? Things like METHOD_NOT_ALLOWED will still have different behavior. Hopefully no one uses those.

[snyamathi]

I think that since the docs are pretty explicit that the status code should be a numerical code I'm okay with the potential to break some people https://github.com/yahoo/fumble#api-docs who are doing otherwise.

It's actually better this way since you'd get e.statusCode = 500 instead of e.statusCode = 'METHOD_NOT_ALLOWED' which makes no sense. It was possible for fumble to return a non-numerical status code before which we will fix with this change.

[lingyan]

sounds good to me.