how to resolve dependency from api.Container

### senario

initialize dependencies
1. dependency: config loader
2. dependency: jwt, it will get config information from config loader

use middleware in dependency jwt

problem is How can i resolve dependencies in main() ?

```go
func main() {
app := iris.New()

//jwtSvc := feature.NewJWTService("your-secret-key", "myxtea")
//app.RegisterDependency(func() feature.JWTService {
// return jwtSvc
//})

feature.ProvideConfigLoader(app)
feature.ProvideDatabase(app)
feature.ProvideJWTService(app)

app.ConfigureContainer(func(api *iris.APIContainer) {

// I can see my dependencies injected before
for _, dependency := range api.Container.Dependencies {
fmt.Println(dependency.String())
}
............

```

it looks there is no such Get ore Resolve method for api.Container

any other solutions?