Is your feature request related to a problem? Please describe.
As highlighted tangentially from #32 erroring on kafka side prints out information about the error to standard out but does not provide the ability to interact with this. Similarly throttle callbacks are not supported in the current implementation of the interface but should be

Describe the solution you'd like
Implement the callback functionality necessary such that q functions .kfk.errorcb and .kfk.throttlecb can be exposed to allow users to handle errors and when a non zero throttle time is received from a broker.

Describe alternatives you've considered
This cannot be handled alternatively to exposure of the functions at a C level with the addition of appropriate q functions to call

Additional resource
An initial implementation of this has been completed although still in beta

• Callback definitions are here, and called by the client definition function here
• q code additions are here