Add covv_host as a new location static field
This PR continues the query implemented in PR 52 regarding counting the different host types in one geographic location.
In this PR we will optimise the existing code by considering a static field is_human_host
as part of the location treap. Next, we will start by checking the static field is_human_host
instead of requesting one DB query for each node. If true, no DB access is required for that node.
The unit and integration tests have already been implemented in PR 52.
Edited by rmuntean