4.15.3

- Disable UPower support by default
- Add 24px and 32px icons
- xfsettingsd: avoid default double fork
- mime: Add 'Open with...' button
- mime: Add new generic launcher icons
- color: Adjust padding of dialog
- color: Add labels to toolbar
- keyboard: Make 'system defaults' a GtkSwitch
- keyboard: Adjust width of shortcut column (Fixes #223)
- keyboard: Update dialog UI
- keyboard: Make all table columns sortable
- keyboard: Improve inline toolbar alignment
- display: Center minimal dialog on monitor where cursor is
- settings-editor: Add labels to toolbar items
- Update README file
- Translation Updates:
  Albanian, Arabic, Armenian (Armenia), Basque, Belarusian, Belarusian
  (Tarask), Bengali, Bulgarian, Catalan, Chinese (China), Chinese (Hong
  Kong), Chinese (Taiwan), Croatian, Czech, Danish, Dutch, Eastern
  Armenian, English (Australia), English (Canada), English (United
  Kingdom), Estonian, Finnish, French, Galician, German, Greek, Hebrew,
  Hungarian, Icelandic, Indonesian, Interlingue, Italian, Japanese,
  Kazakh, Korean, Lithuanian, Malay, Norwegian Bokmål, Norwegian
  Nynorsk, Occitan (post 1500), Polish, Portuguese, Portuguese
  (Brazil), Romanian, Russian, Serbian, Slovak, Slovenian, Spanish,
  Swedish, Thai, Turkish, Ukrainian, Uyghur