An implementation of the server side of JSON-RPC 2.0.
See http://www.jsonrpc.org/specification. This
ByteString for input and output,
leaving the choice of transport up to the user.
Network.JsonRpc.Server module for an example.
json-rpc-server can be used with
to create a client and server that communicate
with the same methods.
Updated the error handling type from ErrorT to ExceptT.
Simplified the call function, so Methods and toMethods are no longer necessary.