Bug 313504: Check validity of i18n calls

Check validity of i18n calls

See:
[...]
Check validity of i18n calls [i18ncheckarg]...OOPS! 4 issues found!

src/widgets/FilenameLayoutWidget.cpp: wrong argument count, have 1 need 0 line# 93 (1)
[...]

The other issues reported in that section are false positives.
src/playlistgenerator/constraints/Checkpoint.cpp: wrong argument count, have 0 need 1 line# 170 (1)
src/playlistgenerator/constraints/TagMatch.cpp: wrong argument count, have 0 need 1 line# 184 (1)
src/playlistgenerator/constraints/TagMatch.cpp: wrong argument count, have 0 need 4 line# 170 (1)
[...]

REVIEW: 112141