[wsgi] Fix unicode decoding in POST
The application/x-www-form-urlencoded sent by firefox or chrome is utf-8
encoded BEFORE being urlencoded.
Hence, decoding must urldecode THEN decode the utf-8 string, and not the
other way around.
Document: cubicweb-doc
Title: CubicWeb documentation
Author: Logilab
Abstract: Some base documentation for CubicWeb users and developpers
Section: Apps/Programming
Format: HTML
Index: /usr/share/doc/cubicweb-documentation/index.html
Files: /usr/share/doc/cubicweb-documentation/*.html