Merge branch 'bootstrap' of https://github.com/PrestaShop/PrestaShop into bootstrap

# By Jérôme Nadaud
# Via Jérôme Nadaud
* 'bootstrap' of https://github.com/PrestaShop/PrestaShop:
  [-] BO : Order template misplaced empty form
  [+] BO : Handler invoice date generation button

controllers/admin/AdminInvoicesController.php

@@ -213,7 +213,7 @@ class AdminInvoicesControllerCore extends AdminController
 
 	public function postProcess()
 	{
-		if (Tools::getValue('submitAddinvoice_date'))
+		if (Tools::isSubmit('submitAddinvoice_date'))
 		{
 			if (!Validate::isDate(Tools::getValue('date_from')))
 				$this->errors[] = $this->l('Invalid "From" date');