New stable release of xfce4-power-manager.

* Bugfixes:
 - plugin:
   - Use libxfce4panel function to obtain desired icon size
   - Fix menu leak, attach menu to button (Bug #13466)
   - Hide label in unknown state (Bug #12851)
   - Add properties dialog (Bug #13270)
   - Set ac-adapter icon for desktop systems (Bug #13959)
   - Hide label by default on desktop systems
   - Block panel autohide if the menu is open
   - Drop deprecated CSS styles
 - Fix xfpm startup dialog ignoring response (Bug #13700)
 - Fix handling of dialog responses for suspend and hibernate (Bug #13405)
 - Set the transient hint for notifications
 - Fix scale description and values for light-locker (Bug #13303)
 - Drop period at end of all tooltip texts (Bug #12342)
 - Make tooltip more concise (Bug #12342)
 - When locking fallback to xflock4 first (Bug #12603)
 - Fix a crash when warning about the screenlocker (Bug #12603)
 - Fix showing inhibits in the systray (Bug #12605)
 - Fix the g_object_bindings in xfce-screensaver
 - Handle screensaver activity with it's own class (Bug #12603)
 - Fix the 3.20 deprecation warnings
 - Use the kernel-supplied backlight type rather than a whitelist (Bug #12553)
 - Fix build on FreeBSD and DragonFlyBSD (Bug #13984)
 - Add MATE to NotShowIn list (Bug #12506)

* Translation updates:
  Arabic, Asturian, Basque, Bulgarian, Catalan, Chinese (China),
  Chinese (Hong Kong), Chinese (Taiwan), Croatian, Czech, Danish,
  Dutch (Flemish), English (Australia), English (Great Britain),
  Estonian, Finnish, French, Galician, German, Greek, Hebrew, Hungarian,
  Icelandic, Indonesian, Italian, Japanese, Kazakh, Korean, Lithuanian,
  Malay, Norwegian Bokmål, Norwegian Nynorsk, Occitan, Polish, Portuguese,
  Portuguese (Brazilian), Romanian, Russian, Serbian, Slovak, Slovenian,
  Spanish, Swedish, Thai, Turkish, Ukrainian, Uyghur, Vietnamese