[fr] app & email
[fr] reorganize all files to follow en version

still english parts to translate
[fr] follow en toc evolutions
Merge pull request #1775 from cakephp/3.0-fr-follow-toc

[fr] follow en toc evolutions
Merge pull request #1776 from cakephp/3.0-fr-review-core-utility-libs

3.0 fr review core utility libs