Updates framework to support automated framework subclasses

All framework classes have been renamed to use the SihnonFramework_ prefix.
The class autoloader now looks for subclasses of the framework classes in the Sihnon_Lib directory, and
automatically creates them if they don't exist. The autoloader correctly creates interfaces and abstract
classes as needed, by using reflection to check the type of the parent class.
All references to classes within the framework now use the Sihnon_ prefix.
The PluginFactory supports multiple scan directories, and will search both the framework and subclass class
tree to find candidate plugins.

source/lib/SihnonFramework/Log/PluginFactory.class.php

@@ -0,0 +1,30 @@
+<?php
+
+class SihnonFramework_Log_PluginFactory extends Sihnon_PluginFactory {
+    
+    protected static $plugin_prefix    = 'Sihnon_Log_Plugin_';
+    protected static $plugin_interface = 'Sihnon_Log_IPlugin';
+    protected static $plugin_dir       = array(
+    	SihnonFramework_Lib => 'SihnonFramework/Log/Plugin/',
+    	Sihnon_Lib          => 'Sihnon/Log/Plugin/',
+	);
+    
+    public static function init() {
+        
+    }
+    
+    public static function create($plugin, $options) {
+        self::ensureScanned();
+        
+        if (! self::isValidPlugin($plugin)) {
+            throw new Sihnon_Exception_InvalidPluginName($plugin);
+        }
+        
+        $classname = self::classname($plugin);
+        
+        return call_user_func(array($classname, 'create'), $options);
+    }
+    
+}
+
+?>