Add Server#create_nic method to quickly create NICs for a Server
Add DataCenter#create_storage and DataCenter#create_load_balancer
Updating a Server doesn't require :cores or :ram parameters
Add check for option :bus_type in Storage#connect
Merge pull request #13 from smarchive/storage_bus_scsi

Add check for option :bus_type in Storage#connect
Merge pull request #12 from smarchive/server_update

Updating a Server doesn't require :cores or :ram parameters
Merge pull request #10 from smarchive/helper_methods

Helper methods for creating Storage, LoadBalancer, and Nic