add missing word; add missing link
add some separation
no need to duplicate what can be referenced
some PEP-8 fixes

* stdlib imports appear first
* top-level functions separated with 2 blank lines
* limit line length to 79 characters
use a context manager so that it does resource cleanups for us
counting starts from zero
no need for strong language
Take advantage of 'literalinclude' and 'lines' directive

This results in less duplication
Merge pull request #10 from tshepang/improve

various improvements to Pyramid Single File Tasks Tutorial
thank you