Feature Request - Opsgenie Sink: Update to support full API v2 options

[jeverett1522]

Currently you are only supporting a few alert options for Opsgenie but there are other fields that would be useful in an alert creation such as entity or responders. Here is the current API json of alert creation:

{
    "message": "<string>",
    "user": "<string>",
    "note": "<string>",
    "source": "<string>",
    "alias": "<string>",
    "description": "<string>",
    "responders": [
        {
            "type": "<string>",
            "id": "<string>"
        },
        {
            "type": "<string>",
            "id": "<string>"
        }
    ],
    "visibleTo": [
        {
            "type": "<string>",
            "id": "<string>"
        },
        {
            "type": "<string>",
            "id": "<string>"
        }
    ],
    "actions": [
        "<string>",
        "<string>"
    ],
    "tags": [
        "<string>",
        "<string>"
    ],
    "details": "<object>",
    "entity": "<string>",
    "priority": "<string>"
}

It would be nice to be able to use the full features of Opsgenie to better use the information in the alert.