[docs] simplify int() signature docs (issue 16036)

[ezio.melotti at gmail.com]

http://bugs.python.org/review/16036/diff/6073/Doc/library/functions.rst
File Doc/library/functions.rst (right):

http://bugs.python.org/review/16036/diff/6073/Doc/library/functions.rst#newcode637
Doc/library/functions.rst:637: For floating point numbers, this
truncates towards zero.
On 2012/09/27 11:06:39, storchaka wrote:
> I don't know if it worth to mention specifically such details.
Floating pointer
> numbers truncated first and then __int__() method called for result.

This was already there.  I think the goal is to say that int() can be
used to "extract" the integer part and that e.g. int(3.7) will return 3,
without doing any rounding.

http://bugs.python.org/review/16036/