* rename dtde to aztk, rename thunderbolt to aztk
* rename azb to aztk, fix bug with --wait
* changed exception to AztkError
* Fix issue with wait flag if not set
## ssh update:
enabled jupyter, attached user to the cluster lvl (as opposed to job level)
## features:
* new cli cmd: spark-cluster-create-user (create user is needed because we cannot automatically create a user on pool creation since we don't necessarily wait for cluster creation to finish)
* new cli cmd: spark-cluster-jupyter
* new cli cmd: spark-cluster-webui
* spark-cluster-ssh does not tunnel any ports by default