Options parameter is recognized on webserver.listen but ignored

Our implementation of httpd.js does not support keep-alive connection.
Oups, fixed regression caused by commit 7df55360
Request object given by WebServer should be writable

Conformance with PhantomJS.
update release notes
Release of SlimerJS 0.9.3
Bumped version to 0.9.4pre and fixed the download page
Webserver: request.post was not set correctly with url encoded content

When the content type of the request is "application/x-www-form-urlencoded",
request.post was suppose to be an object with all parameters. Instead it
was the raw content.

Closes #228
Fix: cookies set with phantom or webpage were not visible in document.cookie
Merge branch 'v0.9'

Conflicts:
	docs/conf.py
	src/application.ini
	src/modules/webserver.jsm
Fixed undefined variable into slConfiguration

Closes #232