Missing custom API Gateway Responses

Hi there,

We've got almost all the error responses customized accept for the ones in this function: https://github.com/aws/chalice/blob/8139001a7ebe27ae3d9f39f34db06b82ebb4d1e4/chalice/app.py#L1613-L1670

Is there a way to override these error responses? Or include them as Classes like the ChaliceViewErrors?

Start in chalice/app.py at lines 1613-1670 and compare the existing error-response handling with the ChaliceViewErrors classes. Trace how custom error responses are currently configured, then define what support is needed for these responses to be overridden or represented as classes. Done means the previously uncovered API Gateway error responses can be customized consistently with the existing mechanism.

Written by the indexing model from the issue text.