[docs] [issue13510] Clarify that readlines() is not needed to iterate over a file

[Ezio Melotti]

Changes by Ezio Melotti <ezio.melotti at gmail.com>:


----------
keywords: +easy
versions: +Python 3.4

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue13510>
_______________________________________