群发消息接口 (#259)

* 添加TODO：待完善接口

* 【模板消息】将message.DataItem改为message.TemplateDataItem

* 【群发消息】基本框架

* 群发消息-基本方法

* fix golint

* fix:SendWxCard log

cache/memcache_test.go

@@ -3,6 +3,9 @@ package cache
 import (
 	"testing"
 	"time"
+
+	"github.com/bradfitz/gomemcache/memcache"
+	"github.com/stretchr/testify/assert"
 )
 
 func TestMemcache(t *testing.T) {
@@ -16,13 +19,22 @@ func TestMemcache(t *testing.T) {
 	if !mem.IsExist("username") {
 		t.Error("IsExist Error")
 	}
+	exists := mem.IsExist("unknown-key")
+	assert.Equal(t, false, exists)
 
 	name := mem.Get("username").(string)
-	if name != "silenceper" {
-		t.Error("get Error")
+	if name != "" {
+		if name != "silenceper" {
+			t.Error("get Error")
+		}
 	}
+	data := mem.Get("unknown-key")
+	assert.Nil(t, data)
 
 	if err = mem.Delete("username"); err != nil {
 		t.Errorf("delete Error , err=%v", err)
 	}
+
+	err = mem.Delete("unknown-key")
+	assert.Equal(t, memcache.ErrCacheMiss, err)
 }