amélioration formulaire

ensiie-project/src/Controller/login.php

ensiie-project/src/Controller/set_utilisateur.php

ensiie-project/src/View/connexion_form.php

ensiie-project/src/View/evenement_form.php

ensiie-project/src/View/head.php

ensiie-project/src/View/media/css/additional.css

...oject/src/View/media/css/ie10-viewport-bug-workaround.css

ensiie-project/src/View/media/images/logo-arise-white-ok.png

ensiie-project/src/View/media/js/additional.js

ensiie-project/src/View/media/js/bootstrap.min.js

...project/src/View/media/js/ie10-viewport-bug-workaround.js