func (csv CSVIntSlice) EncodeValues(key string, v *url.Values) error {
	strCSV := make(CSVStringSlice, len(csv))
	for i, v := range csv {
		strCSV[i] = strconv.Itoa(v)
	}
	return strCSV.EncodeValues(key, v)
}
EncodeValues conforms to query.Encoder inteface
package vkapi
import (
	"errors"
	"net/url"
	"strconv"
	"strings"
	"github.com/mailru/easyjson/jlexer"
)
type CSVStringSlice []string
func (csv CSVStringSlice) EncodeValues(key string, v *url.Values) error {
	if val := []string(csv); len(val) != 0 {
		encoded := strings.Join(val, ",")
		v.Set(key, encoded)
	}
	return nil
}
type CSVIntSlice []int