Handle plugin panics gracefully

[olanod]

Currently a panic in a plugin crashes the whole program. We need some sort of supervisor that can handle a panic in a macro and return an error response instead.

I'm not sure if one can wrap a function that panics and handle the panic or if it has to be done for the whole thread which would mean there would need to be a thread for request handling that should be restarted reloading the relevant plugins.