reorganize code

main.go

@@ -3,12 +3,13 @@ package main
 import (
 	"fmt"
 	"go-nkode/core/api"
+	"go-nkode/core/nkode"
 	"log"
 	"net/http"
 )
 
 func main() {
-	nkodeApi := api.NewNKodeAPI()
+	nkodeApi := nkode.NewNKodeAPI()
 	handler := api.NKodeHandler{Api: nkodeApi}
 	mux := http.NewServeMux()
 	mux.Handle(api.CreateNewCustomer, &handler)