No chef roles and included hadoopstack cookbook

* Removed role dependency by using hadoopstack cookbook. Deleted
create_role().
* Creating nodes with nodename format
"<cluster_id>-<hadoop_role>-<num>"

Signed-off-by: Shashank Sahni <shredder12@gmail.com>
Chef Server setup script

* Installs chef-server and client on Ubuntu.
* Configures client and creates chef-user ubuntu.
* Downloads {hadoop, hadoopstack} cookbooks and uploads them to chef
server.

Signed-off-by: Shashank Sahni <shredder12@gmail.com>