Message type: std_msgs.msg.String (Defines the message structure)
Queue Size: How many messages can be queued for transmission
Rate: How often the message is transmitted in Hz
Is this required? The data can be pushed at the rate it comes in. It will just have to be time stamped.
Could have an YAML options to say periodic and then request a rate. This could be good for a publisher grabbing information from a position sensor or something like that.