func Server(conn net.Conn, config *Config) *Conn {
	return &Conn{conn: conn, config: config}
}
Server returns a new TLS server side connection
using conn as the underlying transport.
The configuration config must be non-nil and must include
at least one certificate or else set GetCertificate.
package tls
import (
	"crypto"
	"crypto/ecdsa"
	"crypto/rsa"
	"crypto/x509"
	"encoding/pem"
	"errors"
	"fmt"
	"io/ioutil"
	"net"
	"strings"
	"time"
)