* Add FileAssociationHelper.cs

* Add register file types option to gtk

* Add register file types option to avalonia

* Add Windows support to FileAssociationHelper.cs

* linux: Add uninstall support for file types

* Ignore .glade~ backup files

* Rename Register/Unregister methods

* gtk: Add manage file types submenu

* ava: Add manage file types submenu

* windows: Add uninstall support for file types

* Don't invert uninstall condition (formatting change)

Co-authored-by: gdkchan <gab.dark.100@gmail.com>

* Add IsTypesRegisteredWindows & Fix Windows install function

* Add AreMimeTypesRegisteredLinux()

* Fix wrong indention

Co-authored-by: AcK77 <acoustik666@gmail.com>
Co-authored-by: gdkchan <gab.dark.100@gmail.com>