Log request context when debug is turned on

[EliAndrewC]

Sideboard has a debug config option which toggles a couple of behaviors. For example, on exceptions we return a full stacktrace in the RPC response when debug is set, but otherwise we only return the error message.

We should add onto this and log the entire request contents, e.g. the entire RPC request when debug is set to true. This would help us out in development where a staging server gets a weird exception we don't expect and we didn't have logging turned up high enough to see the entire request.