[l10n] Update Polish translation

1 missing string, target version
Merge pull request #394 from adsr303/plpo

[l10n] Update Polish translation
Remove old GTK3 checks

we have the same in another place, too
Don't compile with -Werror from source package
matter of taste - modules or modulen
Merge pull request #395 from MRIG/master

matter of taste - modules or modulen
dng writer: fix rounding bug in rational conversion
Fix check for empty multi-name.

Part of #9716.
Fix operation name check in export with a style.

A style name as returned by dt_styles_get_item_list can have a multi-name
catenated. The check to find the corresponding module now take only the
len for the operation.

Fixes #9716.
Merge branch 'fix-export-style'

* fix-export-style:
  Fix operation name check in export with a style.
  Fix check for empty multi-name.
[l10n] Update of Ukrainian translation
small improvement
Merge pull request #396 from MRIG/master

small improvement tooltip
GraphicsMagick: limit gm support to specific filename extensions

RAWs are excluded as GraphicsMagick would render them with third party
libraries in reduced quality - slow and only 8-bit