Exposes reload command via IPublicAPI

Wox.Plugin/IPublicAPI.cs

@@ -62,6 +62,14 @@ namespace Wox.Plugin
         /// </summary>
         void SaveAppAllSettings();
 
+        /// <summary>
+        /// Reloads any Plugins that have the 
+        /// IReloadable implemented. It refeshes
+        /// Plugin's in memory data with new content
+        /// added by user.
+        /// </summary>
+        void ReloadPluginData();
+
         /// <summary>
         /// Show message box
         /// </summary>