Mention unsigned types in doc
Mention unsigned types in doc

rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website,gotthardp/rabbitmq-website,gotthardp/rabbitmq-website,rabbitmq/rabbitmq-website,gotthardp/rabbitmq-website,gotthardp/rabbitmq-website,gotthardp/rabbitmq-website,rabbitmq/rabbitmq-website,gotthardp/rabbitmq-website