Version 13
Changes in this version:
- update metadata.json, fix point release support
- add support for the Gnome 41 #25
- replace all references to Lang.bind() (13)
- update build script to remove unnecessary files (.po, .h, etc)
- move all code within class (nothing in init() or in global scope other than localization)
- fix tray icon switching
- remove non-functional map