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/Config.class.php

@@ -0,0 +1,90 @@
+<?php
+
+class SihnonFramework_Config {
+    
+    /**
+     * Boolean value type
+     * @var bool
+     */
+    const TYPE_BOOL        = 'bool';
+    
+    /**
+     * Integer value type
+     * @var int
+     */
+    const TYPE_INT         = 'int';
+    
+    /**
+     * Float value type
+     * @var float
+     */
+    const TYPE_FLOAT       = 'float';
+    
+    /**
+     * String value type
+     * @var string
+     */
+    const TYPE_STRING      = 'string';
+    
+    /**
+     * String List value type; list of newline separated strings
+     * @var array(string)
+     */
+    const TYPE_STRING_LIST = 'array(string)';
+    
+    /**
+     * Backend to be used for this Config object
+     * @var Sihnon_Config_IPlugin
+     */
+    private $backend;
+
+    /**
+     * Associative array of settings loaded from the database
+     * @var array(string=>array(string=>string))
+     */
+    private $settings       = array();
+
+    /**
+     * Constructs a new instance of the Config class
+     *
+     * @param string $backend Backend to use for storing and retrieving configuration items
+     * @param mixed $options Parameters to configure the Config backend
+     * @return Sihnon_Config
+     */
+    public function __construct($backend, $options) {
+        $this->backend = Sihnon_Config_PluginFactory::create($backend, $options);
+        $this->settings = $this->backend->preload();
+    }
+
+    /**
+     * Identifies whether the named setting exists
+     * 
+     * @param string $key Name of the setting
+     * @return bool
+     */
+    public function exists($key) {
+        return isset($this->settings[$key]);
+    }
+
+    /**
+     * Fetches the value of the named setting
+     * 
+     * @param string $key Name of the setting
+     */
+    public function get($key) {
+        if (!isset($this->settings[$key])) {
+            throw new Sihnon_Exception_UnknownSetting($key);
+        }
+
+        switch ($this->settings[$key]['type']) {
+            case self::TYPE_STRING_LIST:
+                return array_map('trim', explode("\n", $this->settings[$key]['value']));
+                
+            default:
+               return $this->settings[$key]['value'];
+        }
+    }
+
+};
+
+?>