Sway-input-config

Localization support:

- added Russian, Belarusian and Ukranian translations
- added locale-gen script and instructions for translators

Fixed various UI layout issues
Added `--locale` option to launch app with specific localization
Added `--restore` option to reset any settings
Added check for Sway version for disable unsupported features (e.g. disable-while-trackpointing on Sway 1.7 and lower)
Added [touсhpad events](https://wayland.freedesktop.org/libinput/doc/latest/configuration.html#send-events-mode) option
Added [click method](https://wayland.freedesktop.org/libinput/doc/latest/clickpad-softbuttons.html#clickpad-softbuttons) option (only for clickpads)

Fix RadioButtons on all pages

New UI using Qt Designer's forms.
New keyboard layout/variant selection widget
New disable while trackpointing option for touchpad (introduced in libinput 1.6 and Sway 1.8)
New option to configure input device ID's (for per-device settings)
Added option to restore default settings
Config files for Sway now automatic added or removed depending on selection of "Use this settings" option

Store `xkb_layout` and `xkb_variant` in correct values

Fix JSON path

Set app_id to "sway-input-config"