text: Title: Adding multiple classification heads to train in single model
  Body: I want to train a model based on the same architecture but two different classification heads where one would detect layout of documents as table, text, title, figure etc and  other would detect cells inside table. Right now I have two different models for layout and table-cell based on the same architecture. 
  Since I have used the same architecture for both different use-cases. How can I train one single model with combination of layout and cells inside table?
  
  NOTE: I already used OCR coordinates of text inside tables but results were not good enough,so don't want to use it. 