Merge pull request #206 from StefTweet/master

Updated at 14/11/2012 and 15/11/2012 of  symfony / symfony-docs
translation form/create_form_type_extension
Minor tweaks after PR #206
Typo fix by @Garfield-fr in PR #208 (cannot be merged : github bug?)
Merge pull request #209 from gregquat/master

Cookbook/form/type_ext translation + typo fixes