FEAT #202 fusion M2M refactoring

.../sendmail/Controllers/MessageExchangeReviewController.php

...es/sendmail/Controllers/ReadMessageExchangeController.php

...sendmail/Controllers/ReceiveMessageExchangeController.php

...es/sendmail/Controllers/SendMessageExchangeController.php

modules/sendmail/mail_form.php

modules/sendmail/sendmail_ajax_content.php

src/app/basket/models/BasketModelAbstract.php

src/app/contact/models/ContactModelAbstract.php

src/app/entity/models/EntityModelAbstract.php

src/app/note/models/NoteModelAbstract.php

src/app/user/models/UserModelAbstract.php