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/HTMLModule/Ruby.php

@@ -0,0 +1,36 @@
+<?php
+
+/**
+ * XHTML 1.1 Ruby Annotation Module, defines elements that indicate
+ * short runs of text alongside base text for annotation or pronounciation.
+ */
+class HTMLPurifier_HTMLModule_Ruby extends HTMLPurifier_HTMLModule
+{
+
+    /**
+     * @type string
+     */
+    public $name = 'Ruby';
+
+    /**
+     * @param HTMLPurifier_Config $config
+     */
+    public function setup($config)
+    {
+        $this->addElement(
+            'ruby',
+            'Inline',
+            'Custom: ((rb, (rt | (rp, rt, rp))) | (rbc, rtc, rtc?))',
+            'Common'
+        );
+        $this->addElement('rbc', false, 'Required: rb', 'Common');
+        $this->addElement('rtc', false, 'Required: rt', 'Common');
+        $rb = $this->addElement('rb', false, 'Inline', 'Common');
+        $rb->excludes = array('ruby' => true);
+        $rt = $this->addElement('rt', false, 'Inline', 'Common', array('rbspan' => 'Number'));
+        $rt->excludes = array('ruby' => true);
+        $this->addElement('rp', false, 'Optional: #PCDATA', 'Common');
+    }
+}
+
+// vim: et sw=4 sts=4