Adding units to a group

The request is intended for adding an object to a group.

&svc=add_units_to_group&params={
    "group_id": integer,
    "unit_ids": [integer,integer,...]
}

{
    "added": [
        ... //IDs of objects that were added to the group
    ],
    "denied": [
        ... //IDs of objects that were not added to the group
    ]
}