Update Swedish locale with 'printing_not_ready' string
Update zh-TW locale for printing not ready message
Squashed commits to Polish viewer.properties.
(Removed English leftovers)
Updating Dutch translation with print warning
Merge pull request #3010 from piotrex/patch-2

Update Polish viewer.properties (translated "printing_not_ready")
Merge pull request #3011 from Snuffleupagus/printing-not-ready

Update Swedish locale with 'printing_not_ready' string
Merge pull request #3013 from xavier114fch/zh-TW

Update zh-TW locale for printing not ready message
Merge pull request #3014 from timvandermeij/print-warning-dutch

Updating Dutch translation with print warning