system-property "boot-time" attribute should be boolean

/system-property=*/:read-operation-description(name=add)
{
    "outcome" => "success",
    "result" => {
        "operation-name" => "add",
        "description" => "Adds a system property or updates an existing one.",
        "request-properties" => {
            "value" => {
                "type" => STRING,
                "description" => "The value of the system property.",
                "required" => false,
                "nillable" => true
            },
            "boot-time" => {
                "type" => STRING,
                "description" => "If true the system property is passed on the command-line to the started server jvm. If false, it will be pushed to the server as part of the startup sequence.",
                "required" => false,
                "nillable" => true,
                "default" => true
            }
        },
        "reply-properties" => {},
        "read-only" => false
    }
}