feat(config): enable or disable httpd server. (#262)

config/config.go

@@ -20,6 +20,7 @@ type ConfYaml struct {
 
 // SectionCore is sub section of config.
 type SectionCore struct {
+	Enabled         bool           `yaml:"enabled"`
 	Port            string         `yaml:"port"`
 	MaxNotification int64          `yaml:"max_notification"`
 	WorkerNum       int64          `yaml:"worker_num"`
@@ -128,6 +129,7 @@ func BuildDefaultPushConf() ConfYaml {
 
 	// Core
 	conf.Core.Port = "8088"
+	conf.Core.Enabled = true
 	conf.Core.WorkerNum = int64(runtime.NumCPU())
 	conf.Core.QueueNum = int64(8192)
 	conf.Core.Mode = "release"