Teaching notes from Day 1 Shell and Python

Supplemental notes from the Shell and Python units of the first day of the Software Carpentry Bootcamp. The shell has some annotations that weren't present in the live coding we did during the session. The python notes are simply a copy of the ipython notebook developed during the class.
Merge pull request #3 from abostroem/teacher-notes-day-1

Teaching notes from Day 1 Shell and Python