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/Time.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace ZK;
+
+use ZKLib;
+
+class Time
+{
+    /**
+     * @param ZKLib $self
+     * @param string $t Format: "Y-m-d H:i:s"
+     * @return bool|mixed
+     */
+    public function set(ZKLib $self, $t)
+    {
+        $self->_section = __METHOD__;
+
+        $command = Util::CMD_SET_TIME;
+        $command_string = pack('I', Util::encodeTime($t));
+
+        return $self->_command($command, $command_string);
+    }
+
+    /**
+     * @param ZKLib $self
+     * @return bool|mixed
+     */
+    public function get(ZKLib $self)
+    {
+        $self->_section = __METHOD__;
+
+        $command = Util::CMD_GET_TIME;
+        $command_string = '';
+
+        $ret = $self->_command($command, $command_string);
+
+        if ($ret) {
+            return Util::decodeTime(hexdec(Util::reverseHex(bin2hex($ret))));
+        } else {
+            return false;
+        }
+    }
+}