Document TimeHelper::nice takes $format as param

As per the [TimeHelper::nice source code](https://github.com/cakephp/cakephp/blob/master/lib/Cake/Utility/CakeTime.php#L349), it can take $format as param. 

So Document that in the book.
begin translation 'Html' chapter
translation HtmlHelper into Japanese
[ja]translated models/behaviors section
[ja]translated models/callback-methods section
[ja]applied changes around core-libraries.rst
Added note about handling plugin assets through Dispatcher is inefficient
Moved url rewriting to a separate file
Added a section about what if you can't use url rewriting
Improved core config section about App.baseUrl
Added section in deployment about improving performance due to symlinking
Removed parts of the blog tutorial (duplicated content)

Fixed toctrees and a typo

deleted two .DS_Store files

Fixed broken commits
update core librairies.rst and tutorials-and-examples/blog/blog.rst
Update conventions around view files.
Strengthen language.
Convert very to strongly.
Show isUnique as a Model method.

Refs #126
fixed flash parameter type

url parameter is not only string according to the api docs:
http://api.cakephp.org/class/controller#method-Controllerflash
Fix code example.
Added self HABTM documentation
Fix code example
Fixed wrong parameters of Cache::write
Adding docs for multiple counterCache
Added App::uses() and an explanation to the model defintion example
Added App::uses() and an explanation to the model defintion example