Issue LIBCLOUD-416: Improvements to SoftLayer compute driver

A few improvements on the SoftLayer driver.
Fix list_locations
add more templates on list_sizes and fix create_node size related args, 
return more info for nodes on list_nodes
add ex_start_node and ex_stop node
fix states -add machine gets into pending state and halted/paused to unknown form terminated state


https://issues.apache.org/jira/browse/LIBCLOUD-416