remove ipython tricks, these are listed in the introduction
shift discussion of the assignment operator into the basic types section

This feels like a more natural place for this kind of content, since it
discusses the differences between mutable and immutable objects. This follows
nicely from the previous discussion on ints and lists and so on.
minor syntax changes
remove trailing whitespace
overhaul the section on numerical types

This was a bit of an incoerent mess. I streamlined the information and the
layout/ordering. Also, included a link to information about the changed integer
division behaviour in Python 3.
clean up section on lists
use a less ambiguous example when working with lists

Using ints in an example list may be confusing, use colors instead.
minor tweaks to the string section
remove the list notation from tuples and sets
remove trailing whitespace
coherent prompt
proper numbering in the ipythin prompt
remove this footnote, it is confusing
syntax and markup in control flow section
solution for the Wallis formula
trailing whitespace
expand the warning about mutable keyword args
markup and tabs
fibonaci before quicksort
remove trailing whitespace