func GetGenerator() *generator {
	return &gen
}
GetGenerator returns generator struct pointer
generator is single and created only once
package generator
import (
	"fmt"
	"math/rand"
	"os"
	"sync/atomic"
	"github.com/intel-go/nff-go/flow"
	"github.com/intel-go/nff-go/packet"
)
var gen generator
type generator struct {
	count uint64
}