Add reload command for plugins and add to gui

src/common/plugin.h

@@ -164,6 +164,7 @@ struct _hexchat_plugin
 #endif
 
 char *plugin_load (session *sess, char *filename, char *arg);
+int plugin_reload (session *sess, char *name, int by_filename);
 void plugin_add (session *sess, char *filename, void *handle, void *init_func, void *deinit_func, char *arg, int fake);
 int plugin_kill (char *name, int by_filename);
 void plugin_kill_all (void);