Add ZK library classes for device interaction and user management

- Implemented Os class for retrieving OS information.
- Added Pin class for getting PIN width.
- Created Platform class for fetching platform details and version.
- Developed SerialNumber class to retrieve device serial number.
- Introduced Ssr class for SSR information retrieval.
- Implemented Time class for setting and getting device time.
- Added User class for user management including setting, getting, clearing, and removing users.
- Created Util class with various utility functions for command handling and data processing.
- Implemented Version class for fetching device version.
- Added WorkCode class for retrieving work code information.
- Set up Composer autoloading for the ZK library.

zklib/vendor/composer/autoload_psr4.php

@@ -0,0 +1,10 @@
+<?php
+
+// autoload_psr4.php @generated by Composer
+
+$vendorDir = dirname(dirname(__FILE__));
+$baseDir = dirname($vendorDir);
+
+return array(
+    'ZK\\' => array($baseDir . '/src'),
+);