Stop printing "swizzle" and "Connection ID: %d".
Add little script to print a few fields from peninfo.

I'm using this script to measure clock drift of a few pens.
Merge remote-tracking branch 'yonran/get-time' into HEAD

* yonran/get-time:
  Add little script to print a few fields from peninfo.
  Stop printing "swizzle" and "Connection ID: %d".
setup.py: drop build_ext
auto detach kernel driver
add simple notebook-to-pdf converter