Support comma separated multiple routingKey
Handle potential error closing already closed channels on timeouts
Merge branch 'issue-54' of https://github.com/ydh0120/mule-transport-amqp into ydh0120-issue-54
Merge branch 'ydh0120-issue-54' into MULE-7811

Conflicts:
	src/main/java/org/mule/transport/amqp/internal/connector/AmqpConnector.java