pushy.go
func (p *Pushy) DevicePresence(deviceID ...string) (*DevicePresenceResponse, *Error, error) {
	url := fmt.Sprintf("%s/devices/presence?api_key=%s", p.APIEndpoint, p.APIToken)
	var devicePresenceResponse *DevicePresenceResponse
	var pushyErr *Error
	err := post(p.httpClient, url, DevicePresenceRequest{Tokens: deviceID}, &devicePresenceResponse, &pushyErr)
	return devicePresenceResponse, pushyErr, err
}
func (p *Pushy) DevicePresence(deviceID ...string) (*DevicePresenceResponse, *Error, error) {
	url := fmt.Sprintf("%s/devices/presence?api_key=%s", p.APIEndpoint, p.APIToken)
	var devicePresenceResponse *DevicePresenceResponse
	var pushyErr *Error
	err := post(p.httpClient, url, DevicePresenceRequest{Tokens: deviceID}, &devicePresenceResponse, &pushyErr)
	return devicePresenceResponse, pushyErr, err
}
// DevicePresence returns data about presence of a data