Added 4-bucket life stage graph for jaccard similarity analysis.
Merge branch 'master' of https://github.com/prabhamatta/nlp_github_deliberations

* 'master' of https://github.com/prabhamatta/nlp_github_deliberations:
  clean up redundant files
  wip
  added alive and dead user stuff
  cleanup
  added charts
  updated bitcoin usage analysis
  lexical innovations script wip and bitcoin vocabulary
  data extraction updated
  changes in some features
  Adding analyze_conversations to calculate stats for newcomers, core, non-core, mentions and non-mentions