lib.helpers.country: add slovenian language
lib.helpers.country: add slovenian language

shadowoneau/skylines,shadowoneau/skylines,Harry-R/skylines,kerel-fs/skylines,skylines-project/skylines,kerel-fs/skylines,skylines-project/skylines,skylines-project/skylines,snip/skylines,Harry-R/skylines,shadowoneau/skylines,Turbo87/skylines,snip/skylines,TobiasLohner/SkyLines,snip/skylines,skylines-project/skylines,RBE-Avionik/skylines,RBE-Avionik/skylines,Harry-R/skylines,kerel-fs/skylines,Harry-R/skylines,shadowoneau/skylines,Turbo87/skylines,Turbo87/skylines,RBE-Avionik/skylines,TobiasLohner/SkyLines,Turbo87/skylines,TobiasLohner/SkyLines,RBE-Avionik/skylines