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/src/Pin.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace ZK;
+
+use ZKLib;
+
+class Pin
+{
+    /**
+     * @param ZKLib $self
+     * @return bool|mixed
+     */
+    public function width(ZKLib $self)
+    {
+        $self->_section = __METHOD__;
+
+        $command = Util::CMD_DEVICE;
+        $command_string = '~PIN2Width';
+
+        return $self->_command($command, $command_string);
+    }
+}