[CORE] Move core plugins to a new modules directory

For reference (raised by rozzin in IRC):

* http://foldoc.org/module
* http://foldoc.org/library
* http://foldoc.org/plugin

As noted by XRevan86, modules are not necessarily non-essential.
As we will keep the modules directory in GS root [therefore, near to
plugins/], it is evidenced the difference between both.

This is a simple yet fundamental structural change. It doesn't change
functionality but makes clearer the way we understand GNU social's
internals.

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/bitcoin.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * Validates bitcoin (Bitcoin addresses)
+ * @todo validate address length and stuff
+ */
+
+class HTMLPurifier_URIScheme_bitcoin extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $may_omit_host = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        $uri->host     = null;
+        $uri->port     = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/geo.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * Validates geo (geographical coordinates) according to RFC 5870
+ * @todo Filter allowed query parameters and their order
+ */
+
+class HTMLPurifier_URIScheme_geo extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $may_omit_host = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        $uri->host     = null;
+        $uri->port     = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/gopher.php

@@ -0,0 +1,36 @@
+<?php
+
+/**
+ * Validates gopher
+ */
+class HTMLPurifier_URIScheme_gopher extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type int
+     */
+    public $default_port = 70;
+
+    /**
+     * @type bool
+     */
+    public $browsable = true;
+
+    /**
+     * @type bool
+     */
+    public $hierarchical = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/irc.php

@@ -0,0 +1,36 @@
+<?php
+
+/**
+ * Validates irc
+ */
+class HTMLPurifier_URIScheme_irc extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type int
+     */
+//    public $default_port = 6667;
+
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $hierarchical = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/ircs.php

@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * Validates irc
+ */
+class HTMLPurifier_URIScheme_ircs extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type int
+     */
+//    public $default_port = 6697;
+
+    /**
+     * @type bool
+     */
+    public $secure = true;
+
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $hierarchical = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/magnet.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * Validates magnet (BitTorrent hash links)
+ * @todo require xt= GET parameter
+ */
+
+class HTMLPurifier_URIScheme_magnet extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $may_omit_host = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        $uri->host     = null;
+        $uri->port     = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4

modules/HTMLPurifierSchemes/lib/htmlpurifier/urischeme/xmpp.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * Validates xmpp (for XMPP, so called JIDs)
+ * @todo Validate the xmpp address
+ */
+
+class HTMLPurifier_URIScheme_xmpp extends HTMLPurifier_URIScheme
+{
+    /**
+     * @type bool
+     */
+    public $browsable = false;
+
+    /**
+     * @type bool
+     */
+    public $may_omit_host = true;
+
+    /**
+     * @param HTMLPurifier_URI $uri
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return bool
+     */
+    public function doValidate(&$uri, $config, $context)
+    {
+        $uri->userinfo = null;
+        $uri->host     = null;
+        $uri->port     = null;
+        return true;
+    }
+}
+
+// vim: et sw=4 sts=4