use %APPDATA%

1. Fix can't find Result.ctor bug for plugin introduced in
c0889de1f9ae460b2cc189eb59e5bd90ddb7d17e
2. use %APPDATA% for all data, part of #389
3. MISC

Wox.Plugin/IPublicAPI.cs

@@ -82,11 +82,6 @@ namespace Wox.Plugin
         /// <param name="path">Plugin path (ends with .wox)</param>
         void InstallPlugin(string path);
 
-        /// <summary>
-        /// Reload all plugins
-        /// </summary>
-        void ReloadPlugins();
-
         /// <summary>
         /// Get translation of current language
         /// You need to implement IPluginI18n if you want to support multiple languages for your plugin