- Extract how slicing is done from Inventory#get_script_data and pull it
into a new method, Inventory#get_sliced_hosts
- Make use of this method in Inventory#get_script_data
- Make use of this method in Job#_get_inventory_hosts (used by
Job#start_job_fact_cache and Job#finish_job_fact_cache).
This fixes an issue (namely in Tower 4.1) where job slicing with fact
caching enabled doesn't save facts for all hosts.
Signed-off-by: Rick Elrod <rick@elrod.me>