fixed lint errors in d2input (#693)

d2core/d2input/input_manager.go

@@ -19,7 +19,8 @@ type inputManager struct {
 	entries handlerEntryList
 }
 
-func New() d2interface.InputManager {
+// NewInputManager returns a new input manager instance
+func NewInputManager() d2interface.InputManager {
 	return &inputManager{
 		inputService: ebiten_input.InputService{},
 	}

main.go

@@ -39,7 +39,7 @@ func main() {
 		panic(err)
 	}
 
-	inputManager := d2input.New()
+	inputManager := d2input.NewInputManager()
 	term, err := d2term.New(inputManager)
 	if err != nil {
 		log.Fatal(err)