Minor changes to Python style guide.

Mostly removing references to the 2015 tutorial, so that it is useful
for the 2016 course.

Author: pmediano

PythonStyleGuide.md

@@ -1,11 +1,10 @@
 Notes about coding style
 -----------------------
 
-As noted by one of your colleagues after the tutorial, good coding style is
+As known by every decent computer scientist ever, good coding style is
 fundamental. It is specially important when someone has to mark your code. To
-help yourself write pretty Python code, your anonymous style-hero classmate and
-I recommend the package `flake8`, that you can easily pip inside your virtual
-environment:
+help yourself write pretty Python code, I recommend the package `flake8`, that
+you can easily pip inside your virtual environment:
 
 ```
 pip install flake8