Can't make this plugin work with Android

Hi,

Looks like I can't make this plugin work with Android. In the SoundManager.gd script at the function get_sound_manager_settings(), there is this code: file.open("res://addons/sound_manager/SoundManager.json", File.READ). In Windows is working fine, but in an Android enviroment the plugin isn't able to load this file. If you put this line inside a print_debug() call, It inform the error ERR_CANT_OPEN (19), but the Godot's documentation doens't help to understand what is going on.

I saw in another plugin that they have an script called export_pluing.gd (extends EditorExportPlugin), which has a overrited function called _export_begin() (which is called by Godot). This method creates a bunch of folders and files (.json and .cfg) when the project is being exported to any platform. I think maybe there is something worth looking at here. This other plugin I'm referencing to is Dialogic.