Update models_list_en.md

doc/doc_en/models_list_en.md

 ## OCR model list（V2.0, updated on 2020.12.12）
+**Note** : Compared with models 1.0, which are trained with static graph programming paradigm, models 2.0 are the dynamic graph trained version and achieve close performance.
 
 - [1. Text Detection Model](#Detection)
 - [2. Text Recognition Model](#Recognition)