Added a rendering commandline tool

This simple tool renders some syntax given on STDIN with the given
renderer (defaults to xhtml) and outputs to STDOUT.

bin/render.php

+#!/usr/bin/php
+<?php
+/**
+ * A simple commandline tool to render some DokuWiki syntax with a given
+ * renderer.
+ *
+ * This may not work for plugins that expect a certain environment to be
+ * set up before rendering, but should work for most or even all standard
+ * DokuWiki markup
+ *
+ * @license GPL2
+ * @author Andreas Gohr <andi@splitbrain.org>
+ */
+if ('cli' != php_sapi_name()) die();
+
+ini_set('memory_limit','128M');
+if(!defined('DOKU_INC')) define('DOKU_INC',realpath(dirname(__FILE__).'/../').'/');
+define('NOSESSION',1);
+require_once(DOKU_INC.'inc/init.php');
+require_once(DOKU_INC.'inc/common.php');
+require_once(DOKU_INC.'inc/parserutils.php');
+require_once(DOKU_INC.'inc/cliopts.php');
+
+// handle options
+$short_opts = 'hr:';
+$long_opts  = array('help','renderer:');
+$OPTS = Doku_Cli_Opts::getOptions(__FILE__,$short_opts,$long_opts);
+if ( $OPTS->isError() ) {
+    fwrite( STDERR, $OPTS->getMessage() . "\n");
+    _usage();
+    exit(1);
+}
+$RENDERER = 'xhtml';
+foreach ($OPTS->options as $key => $val) {
+    switch ($key) {
+        case 'h':
+        case 'help':
+            _usage();
+            exit;
+        case 'r':
+        case 'renderer':
+            $RENDERER = $val;
+    }
+}
+
+
+// do the action
+$source = stream_get_contents(STDIN);
+$info = array();
+$result = p_render($RENDERER,p_get_instructions($source),$info);
+if(is_null($result)) die("No such renderer $RENDERER\n");
+
+
+/**
+ * Print usage info
+ */
+function _usage(){
+    print "Usage: render.php <options>
+
+    Reads DokuWiki syntax from STDIN and renders it with the given renderer
+    to STDOUT
+
+    OPTIONS
+        -h, --help                 show this help and exit
+        -r, --renderer <renderer>  the render mode (default: xhtml)
+";
+}