created plugin custer, and removed shortcodes change_id and user_infos from cipf plugin

plugins/custer/change_id.php

@@ -0,0 +1,58 @@
+<?php
+namespace CUSTER;
+
+/*
+* it means someone outside wp is accessing the file, in this case kill it.
+*/
+if (!defined('ABSPATH')) {
+	die('You can not access this file!');
+}
+
+
+
+
+
+/*
+* change the current user to the author id of the current object
+* the only option is to force the author
+* -> there is no sens in forcing the logged_in, because it's already the default
+*
+* [custer_change_id]         -> default (author)
+* [custer_change_id author]  -> author
+* [custer_change_id off]     -> reset to logged_in
+*
+*/
+function shortcode_change_id($options) {
+	/*
+	* set the default value for option
+	* currently it can only be author
+	*
+	*/
+	$option = 'author';
+	if (is_array($options)) {
+		$option = reset($options);
+	}
+
+	if (!is_string($option)) {
+		return;
+	}
+
+
+	if ($option === 'author') {
+		$id = get_author_id();
+		Custer::set_current_user_backup();
+		wp_set_current_user($id);
+	}
+	else if ($option === 'off') {
+		$id = Custer::reset_current_user_backup();
+		wp_set_current_user($id);
+	}
+	else
+		return;
+}
+add_shortcode('custer_change_id', __NAMESPACE__.'\shortcode_change_id');
+
+
+
+
+?>