Add X13 WebP module for image conversion to next-generation formats

- Implemented the X13Webp class with core functionalities for converting images to WebP format.
- Added support for different PHP versions and defined constants for versioning.
- Included translation strings for various user interface elements and messages.
- Created XML file for module versioning.

modules/x13webp/vendor/composer/autoload_psr4.php

@@ -0,0 +1,16 @@
+<?php
+
+// autoload_psr4.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+    'X13Webp\\' => array($baseDir . '/src'),
+    'WebPConvert\\' => array($vendorDir . '/rosell-dk/webp-convert/src'),
+    'LocateBinaries\\' => array($vendorDir . '/rosell-dk/locate-binaries/src'),
+    'ImageMimeTypeSniffer\\' => array($vendorDir . '/rosell-dk/image-mime-type-sniffer/src'),
+    'ImageMimeTypeGuesser\\' => array($vendorDir . '/rosell-dk/image-mime-type-guesser/src'),
+    'FileUtil\\' => array($vendorDir . '/rosell-dk/file-util/src'),
+    'ExecWithFallback\\' => array($vendorDir . '/rosell-dk/exec-with-fallback/src'),
+);