Fix: uniformise and clean code

htdocs/commande/commande.class.php

htdocs/compta/facture/facture-rec.class.php

htdocs/facture.class.php

htdocs/fichinter/fichinter.class.php

htdocs/fourn/fournisseur.commande.class.php

htdocs/fourn/fournisseur.facture.class.php

htdocs/lib/pdf.lib.php

htdocs/projet/project.class.php

htdocs/propal.class.php