begin to add rabbitmq tutorials

most of these are included in the manual amqp test already, but I wanted
to break them out so users could have a nice example of how to do these
in standalone form, like the python tutorials. Helloworld (tutorial 1) is
also included fully implemented in this commit
add the workqueues tutorial

still incomplete because qos is temporarily disabled
implemented pubsub tutorial
refactor Message

message now provides an "isValid" property, data is implicitly shared now
change the way messages are received

Messages used to be "delivered" and pushed right onto the queue, which
is where the requirement for Message to be explicitly shared came from.
Now messages that are incomplete come in and are stored in a "currentMessage"
private member (there is a requirement that messages are delivered in this
fashion, by the spec). Once the message body has come in, it is put into
the local queue and the messageReceived signal is emitted.

Also, modified Queue to be able to track a number of consumer tags. This
was exposed by the "routing" tutorial, where a single consumer can bind
to a number of exchanges with a generated consumer tag. The previous example
did not run into this problem because it used an explicitly set consumer tag
and therefore there were no conflicts.
added the routing tutorial
added topics tutorial
changed some variable names for clarity and readability