autopep8 --ignore=E501 fixes. Marginal improvement.
Merge remote-tracking branch 'cam/master' into chap7-style
Ending code cells with a semicolon.
Merge branch 'cam-master' into chap7-style
Not adding or removing semicolons
Merge pull request #181 from eli-b/chap7-style

autopep8 --ignore=E501,E703 fixes. Marginal improvement.