Chunking strategy

First experiments show using the xapi chunk strategy delivers better results than the simple pdf page chunk strategy. Maybe we can think of parsing the chunks during the index process (to remove useless chunks if exists)

https://eduplex.atlassian.net/browse/EDX-518

A second experiment with 2 different courses, is showing that xapi performs better than pdf. We noticed that sometimes the chunks do not contain all the needed context to answer all questions and we are getting some questions that are not answered.

1. Future skills
2. Agiles mindset
3. Kritisches denken