cli: Add module to run the CLI server with a router

This adds a command-line module named `serve` which adds a module to run the
command-line built-in PHP server with a router file that will properly
handle the expected URL dispatchers for the pages/, api/, and apps/ magic
URLs.

Usage:

$ php manage.php serve --help

include/cli/modules/serve.php

+<?php
+
+class CliServerModule extends Module {
+    var $prologue = "Run a CLI server for osTicket";
+
+    var $options = array(
+        'port' => array('-p','--port',
+            'default'=>'8000',
+            'help'=>'Specify the listening port number. Default is 8000',
+        ),
+        'host' => array('-h','--host',
+            'default'=>'localhost',
+            'help'=>'Specify the bind address. Default is "localhost"',
+        ),
+    );
+
+    function make_router() {
+        $temp = rtrim(sys_get_temp_dir(), DIRECTORY_SEPARATOR) . DIRECTORY_SEPARATOR;
+        $router_path = $temp
+            . substr(md5('osticket-router'.getcwd()), -12)
+            . '.php';
+
+        // Ensure that the router file is cleaned up on exit
+        $cleanup = function() use ($router_path) {
+            @unlink($router_path);
+        };
+        if (function_exists('pcntl_signal'))
+            pcntl_signal(SIGINT, $cleanup);
+
+        // This will very likely not fire
+        register_shutdown_function($cleanup);
+
+        $fp = fopen($router_path, 'wt');
+        fwrite($fp, <<<EOF
+<?php
+\$full_path = \$_SERVER["DOCUMENT_ROOT"] . \$_SERVER["REQUEST_URI"];
+# Ensure trailing slash on folders
+if (is_dir(\$full_path)
+    && rtrim(\$full_path, '/') == \$full_path
+) {
+    header("Location: " . \$_SERVER["REQUEST_URI"] . '/');
+}
+elseif (file_exists(\$_SERVER['SCRIPT_FILENAME'])) {
+    return false;
+}
+// Support various dispatchers
+elseif (\$offs = stripos(\$_SERVER["REQUEST_URI"], 'scp/apps/')) {
+    \$_SERVER["PATH_INFO"] = substr(\$_SERVER["REQUEST_URI"], \$offs + 8);
+    chdir('scp/');
+    require "apps/dispatcher.php";
+}
+elseif (\$offs = stripos(\$_SERVER["REQUEST_URI"], 'pages/')) {
+    \$_SERVER["PATH_INFO"] = substr(\$_SERVER["REQUEST_URI"], \$offs + 5);
+    require "pages/index.php";
+}
+elseif (\$offs = stripos(\$_SERVER["REQUEST_URI"], 'api/')) {
+    \$_SERVER["PATH_INFO"] = substr(\$_SERVER["REQUEST_URI"], \$offs + 3);
+    require "api/http.php";
+}
+EOF
+        );
+        fclose($fp);
+
+        return $router_path;
+    }
+
+    function run($args, $options) {
+        $router = $this->make_router();
+        $pipes = array();
+        $php = proc_open(
+            sprintf("php -S %s:%s -t %s %s", $options['host'], $options['port'],
+                ROOT_DIR, $router),
+            array(
+                1 => array('pipe', 'w'),
+                2 => array('pipe', 'w'),
+            ), $pipes);
+
+        stream_set_blocking($pipes[1], 0);
+        stream_set_blocking($pipes[2], 0);
+
+        while (true) {
+            if (feof($pipes[1]) || feof($pipes[2])) {
+                fclose($pipes[1]);
+                fclose($pipes[2]);
+                break;
+            }
+            if ($block = fgets($pipes[1], 1024))
+                fwrite(STDOUT, $block);
+            if ($block = fgets($pipes[2], 1024))
+                fwrite(STDERR, $block);
+            usleep(100);
+        }
+    }
+}
+Module::register('serve', 'CliServerModule');