fix the exchange option autoDelete default value to false in README.md
fix the exchange option autoDelete default value to false in README.md

The default value of autoDelete option when creating an exchange is actually false. However, the document says it is true. Fix the document such that it matches the actual behavior.
remind101/node-amqp,seanahn/node-amqp,hinson0/node-amqp,remind101/node-amqp,postwait/node-amqp,postwait/node-amqp,segmentio/node-amqp,zkochan/node-amqp,albert-lacki/node-amqp,zinic/node-amqp,zkochan/node-amqp,xebitstudios/node-amqp,seanahn/node-amqp,postwait/node-amqp,remind101/node-amqp,albert-lacki/node-amqp,zkochan/node-amqp,segmentio/node-amqp,hinson0/node-amqp,hinson0/node-amqp,albert-lacki/node-amqp,xebitstudios/node-amqp,zinic/node-amqp,xebitstudios/node-amqp,zinic/node-amqp