xfce4-taskmanager: update to 1.5.4

Change log:

1.5.4
======
- Update configure.ac.in syntax
- Fix #53: taskmanager translations
- Translation Updates:
  Albanian, Basque, Belarusian, Bulgarian, Catalan, Chinese (China),
  Chinese (Taiwan), Czech, Danish, Dutch, Estonian, French, Galician,
  German, Greek, Hebrew, Indonesian, Italian, Japanese, Kazakh, Korean,
  Lithuanian, Norwegian Bokm奪l, Polish, Portuguese, Portuguese
  (Brazil), Russian, Serbian, Slovak, Spanish, Swedish, Thai, Turkish,
  Ukrainian

1.5.3
======
- Fix rendering bug (Fixes #44)
- Fix rendering bug for swap graph (relates to #44)
- Fix bindings related to the "show-legend" setting
- Allow to copy full process command line (#33)
- Rename Private to Resident Bytes (#7)
- Avoid grabbing the filter entry if it is not realized
- Fix intltool lock file problem during make distcheck
- `uid_name` has been removed from `task` struct
- Fix invalid casts for "About" and "Help" (Fixes #43)
- Show localized website label
- Update COPYING (Issue #49)
- Updated copyright year, authors, and project links
- Translation Updates:
  Albanian, Arabic, Armenian (Armenia), Asturian, Azerbaijani, Basque,
  Belarusian, Bulgarian, Catalan, Chinese (China), Chinese (Hong Kong),
  Chinese (Taiwan), Croatian, Czech, Danish, Dutch, Eastern Armenian,
  English (Australia), English (United Kingdom), Estonian, Finnish,
  French, Galician, German, Greek, Hebrew, Hungarian, Icelandic,
  Indonesian, Interlingue, Italian, Japanese, Kazakh, Korean,
  Lithuanian, Malay, Norwegian Bokm奪l, Occitan (post 1500), Persian
  (Iran), Polish, Portuguese, Portuguese (Brazil), Russian, Serbian,
  Slovak, Spanish, Swedish, Telugu, Thai, Turkish, Ukrainian, Uyghur


(gutteridge)