Spark intro scp command is incomplete

[rashkov]

The spark intro contains the following invalid command:

local_machine:~$ scp -r -i   ubuntu@:~/price_data

It should actually be something like: scp -r -i <PATH_TO_SSH_KEY_FILE> <PATH_TO_PRICE_DATA_FOLDER> ubuntu@<DNS_FOR_MASTER_NODE>:~/price_data