The host index operation fails when not including a :fact_values eager loader
In the case that a user with a fact_filter tries to index the hosts, the operation will fail unless there is an eager load of fact_values.
Eager loading fact_values is slow.
Fixes #443 - remove unnecassary fact_values loading
This fix does not explain why you need to include :fact_values to
avoid an SQL error. However this includes the fact_values when you do
really need them and does not when you don't
Refactored show_hosts and index
Added a test for json + fact filter
Updated default access permsssions to add support for show_hosts functions