Merge pull request #6780 from marcosgdf/php7-warnings

htdocs/core/class/commonobject.class.php

htdocs/core/modules/commande/doc/pdf_einstein.modules.php

htdocs/core/modules/facture/doc/pdf_crabe.modules.php

htdocs/core/modules/propale/doc/pdf_azur.modules.php

.../core/modules/supplier_order/pdf/pdf_muscadet.modules.php

...core/modules/supplier_proposal/doc/pdf_aurore.modules.php

htdocs/theme/eldy/style.css.php