ProtocolVersionRequest => (empty)
 
ProtocolVersionResponse => [ApiKey ApiName [ApiVersion]]
  ApiKey => int16       // API protocol key
  ApiName => string     // Human readable form of API, e.g. "ProduceRequest"
  ApiVersion => int16   // Supported versions in order of preferredness, most preferred version first (thus typically descending order)
                         // A value of -1 in the array should not be treated as a version but a barrier to indicate that any
                        // sub-sequent versions are deprecated, e.g.: [5,4,-1,3,2,1,0] means 5 & 4 are okay while versions 3-0 are deprecated.
 
Example in pseudo format:
 
ProtocolVersionResponse =>
[
 { ApiKey: 0, ApiName: "ProduceRequest", ApiVersion: [2,1,0] },
 { ApiKey: 1, ApiName: "FetchRequest", ApiVersion: [1,0] },
 { ApiKey: 2, ApiName: "OffsetRequest", ApiVersion: [2,0,-1,1] },
  ...
]