BREAKING CHANGES:
- removed resp::Arg trait. From now own, commands expect a type that implements the Serialize trait for more flexibility and to be more standard.
- CommandBuider struct has been introduced to serialize command arguments on the fly into a RESP buffer for less allocations and less copies
- Command struct is now based on a Bytes RESP buffer and a command name & arguments layout to extract in performant way name & arguments on demand.
- All high level commands & network layer have been refactored consequently