func (c *pubSubConn) Subscribe(channel string, pattern bool) error {
	return c.subUnsub(channel, pattern, true)
}
Subscribe subscribes the redis connection to the channel, which may
be a pattern.
package redisbroker
import (
	"encoding/json"
	"expvar"
	"sync"
	"github.com/mna/juggler/broker"
	"github.com/mna/juggler/message"
	"github.com/garyburd/redigo/redis"
)
var _ broker.PubSubConn = (*pubSubConn)(nil)
type pubSubConn struct {
	psc   redis.PubSubConn
	logFn func(string, ...interface{})
	vars  *expvar.Map
	wmu sync.Mutex
	once sync.Once
	evch chan *message.EvntPayload
	errmu sync.Mutex
	err   error
}
func (c *pubSubConn) Close() error {
	return c.psc.Close()
}