Add support for printing shoppinglist with thermal printer (#1273)

* Added escpos-php library

* Added button to shoppinglist print menu

* Added to translation

* Added basic printing logic and API call

* Working implementation for printing with the API

* Added openapi json

* Correctly parsing boolean parameter

* Working button in UI

* Change to grocy formatting

* Add Date

* Only show thermal print button when Feature Flag is set

* Fixed API call and added error message parsing

* Undo translation

* Add flag to print quantities as well

* Added printing notes

* Added quantity conversion

* Increse feed

* Fixed that checkbox was undefined, as dialog was already closed

* Added padding

* Formatting

* Added note about user permission

* Fixed error when using notes instead of products

* Review

- Default FEATURE_FLAG_THERMAL_PRINTER to disabled
- Added missing localization strings (and slightly adjusted one)

* Fixed merge conflicts

Co-authored-by: Bernd Bestel <bernd@berrnd.de>

helpers/PrerequisiteChecker.php

@@ -4,7 +4,7 @@ class ERequirementNotMet extends Exception
 {
 }
 
-const REQUIRED_PHP_EXTENSIONS = ['fileinfo', 'pdo_sqlite', 'gd', 'ctype'];
+const REQUIRED_PHP_EXTENSIONS = ['fileinfo', 'pdo_sqlite', 'gd', 'ctype', 'json', 'intl', 'zlib'];
 const REQUIRED_SQLITE_VERSION = '3.9.0';
 
 class PrerequisiteChecker