Replace existing autoloader with Composer-supplied

- Move Friendica namespace to `src`
- Move required `ezyang/htmlpurifier` to vendor
- Remove existing static autoloader
- Change boot.php reference to the autoloader

vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrTransform/SafeParam.php

@@ -0,0 +1,79 @@
+<?php
+
+/**
+ * Validates name/value pairs in param tags to be used in safe objects. This
+ * will only allow name values it recognizes, and pre-fill certain attributes
+ * with required values.
+ *
+ * @note
+ *      This class only supports Flash. In the future, Quicktime support
+ *      may be added.
+ *
+ * @warning
+ *      This class expects an injector to add the necessary parameters tags.
+ */
+class HTMLPurifier_AttrTransform_SafeParam extends HTMLPurifier_AttrTransform
+{
+    /**
+     * @type string
+     */
+    public $name = "SafeParam";
+
+    /**
+     * @type HTMLPurifier_AttrDef_URI
+     */
+    private $uri;
+
+    public function __construct()
+    {
+        $this->uri = new HTMLPurifier_AttrDef_URI(true); // embedded
+        $this->wmode = new HTMLPurifier_AttrDef_Enum(array('window', 'opaque', 'transparent'));
+    }
+
+    /**
+     * @param array $attr
+     * @param HTMLPurifier_Config $config
+     * @param HTMLPurifier_Context $context
+     * @return array
+     */
+    public function transform($attr, $config, $context)
+    {
+        // If we add support for other objects, we'll need to alter the
+        // transforms.
+        switch ($attr['name']) {
+            // application/x-shockwave-flash
+            // Keep this synchronized with Injector/SafeObject.php
+            case 'allowScriptAccess':
+                $attr['value'] = 'never';
+                break;
+            case 'allowNetworking':
+                $attr['value'] = 'internal';
+                break;
+            case 'allowFullScreen':
+                if ($config->get('HTML.FlashAllowFullScreen')) {
+                    $attr['value'] = ($attr['value'] == 'true') ? 'true' : 'false';
+                } else {
+                    $attr['value'] = 'false';
+                }
+                break;
+            case 'wmode':
+                $attr['value'] = $this->wmode->validate($attr['value'], $config, $context);
+                break;
+            case 'movie':
+            case 'src':
+                $attr['name'] = "movie";
+                $attr['value'] = $this->uri->validate($attr['value'], $config, $context);
+                break;
+            case 'flashvars':
+                // we're going to allow arbitrary inputs to the SWF, on
+                // the reasoning that it could only hack the SWF, not us.
+                break;
+            // add other cases to support other param name/value pairs
+            default:
+                $attr['name'] = $attr['value'] = null;
+        }
+        return $attr;
+    }
+}
+
+// vim: et sw=4 sts=4