fix golint issues, package comments (#454)

core/discov/internal/etcdclient.go

@@ -1,4 +1,5 @@
 //go:generate mockgen -package internal -destination etcdclient_mock.go -source etcdclient.go EtcdClient
+
 package internal
 
 import (

core/discov/internal/updatelistener.go

@@ -1,4 +1,5 @@
 //go:generate mockgen -package internal -destination updatelistener_mock.go -source updatelistener.go UpdateListener
+
 package internal
 
 type (

core/stores/mongo/internal/collection.go

@@ -1,4 +1,5 @@
 //go:generate mockgen -package internal -destination collection_mock.go -source collection.go
+
 package internal
 
 import "github.com/globalsign/mgo"

core/stores/mongo/iter.go

@@ -1,4 +1,5 @@
 //go:generate mockgen -package mongo -destination iter_mock.go -source iter.go Iter
+
 package mongo
 
 import (

tools/goctl/model/sql/test/orm.go

@@ -1,4 +1,5 @@
 // copy from core/stores/sqlx/orm.go
+
 package mocksql
 
 import (

tools/goctl/model/sql/test/sqlconn.go

@@ -1,4 +1,5 @@
 // copy from core/stores/sqlx/sqlconn.go
+
 package mocksql
 
 import (

tools/goctl/model/sql/test/utils.go

@@ -1,4 +1,5 @@
 // copy from core/stores/sqlx/utils.go
+
 package mocksql
 
 import (