text: Title: No alignments file found
  Body: Hi, when i am doing "convert". it tells me No alignments file found.
  The command I used is:
  python3 faceswap.py convert -i ~/faceswap/src/trump/ -o ~/faceswap/converted/ -m ~/faceswap/trump_cage_model/
  
  The console output is :
  03/11/2020 10:39:30 ERROR    No alignments file found. Please provide an alignments file for your destination video (recommended) or enable on-the-fly conversion (not recommended).
  
  I find there is a xx_alignments.fsa file in the input dir. But no alignments.json file. So what should I do then.
  