CE-2576: Limit IOCs per host
A configurable property: monitor.host-max-capacity
has been introduced with default value 20 to limit deployments for a host.
Warning level alerts are shown on the host if there are more than 20 IOCs deployed on it.
If the user attempts to deploy more than 20 IOCs to the target host, an HTTP 412 error is thrown.
Closes CE-2576