缓存驱动更换成功，支持3级缓存，memory，以及db

cache/cache_db.go

@@ -20,13 +20,26 @@ type HoTimeDBInterface interface {
 }
 
 type CacheDb struct {
-	Time int64
-	Db   HoTimeDBInterface
-	Error
+	TimeOut    int64
+	DbSet      bool
+	SessionSet bool
+	Time       int64
+	Db         HoTimeDBInterface
+	*Error
 	ContextBase
 	isInit bool
 }
 
+func (this *CacheDb) GetError() *Error {
+
+	return this.Error
+
+}
+
+func (this *CacheDb) SetError(err *Error) {
+	this.Error = err
+}
+
 func (that *CacheDb) initDbTable() {
 	if that.isInit {
 		return
@@ -146,7 +159,7 @@ func (that *CacheDb) Cache(key string, data ...interface{}) *Obj {
 	}
 	if len(data) == 2 {
 		that.SetError(nil)
-		tempt := ObjToInt64(data[1], &that.Error)
+		tempt := ObjToInt64(data[1], that.Error)
 
 		if tempt > tim {
 			tim = tempt