clean up some files to make enchanced inbox run for first time

workflow/engine/classes/class.plugin.php

@@ -15,7 +15,8 @@ class PMPlugin extends PmPluginCompatibility
     public $sPluginFolder = '';
     public $aWorkspaces = null;
     public $bPrivate = false;
-
+    public $sDescription;
+    public $sSetupPage;
     /**
      * This function sets values to the plugin
      * @param string $sNamespace
@@ -28,6 +29,8 @@ class PMPlugin extends PmPluginCompatibility
         $this->sClassName = $sNamespace . 'Plugin';
         $this->sPluginFolder = $sNamespace;
         $this->sFilename = $sFilename;
+        $this->sDescription = null;
+        $this->sSetupPage = null;
     }
 
     /**