Expand readme, cleanup

[ashander]

Add a line about demo file location; reformat bolding to markdown.

Cleanup

• add .gitignore (right now, just swap files)
• delete eventapi_recovered.py, as it looks almost identical to the first commit of eventapi.py:

  diff <(git show 62388:eventapi.py) eventapi_recovered.py
  25c25
  <     next_time = item['timecode'].strftime('%I:%M')
  ---
  >     next_time = item['timecode']