Add constants to the function set_error_handler

Add constants to the function set_error_handler to improve error
management.
Renamed directory "web" to "www"

Because most of document roots on shared servers are named "www".
Vocabulary : renames "module" attribute of router to "controller"
Namespace problem
adds expire headers and gzip compression
cleaning slug functions
Updating jquery
Merge branch 'master' of https://github.com/studiocaramia/Citrus

Conflicts:
	apps/install/config/view.php