[enh] duckduckgo engine: add language support
[enh] duckduckgo engine: add language support

pointhi/searx,GreenLunar/searx,matejc/searx,kdani3/searx,framasoft/searx,dzc34/searx,dzc34/searx,framasoft/searx,kdani3/searx,framasoft/searx,gugod/searx,jpope777/searx,misnyo/searx,misnyo/searx,jibe-b/searx,potato/searx,jpope777/searx,jibe-b/searx,PwnArt1st/searx,pointhi/searx,asciimoo/searx,jcherqui/searx,misnyo/searx,matejc/searx,jpope777/searx,GreenLunar/searx,jibe-b/searx,dalf/searx,jcherqui/searx,dzc34/searx,dzc34/searx,PwnArt1st/searx,jibe-b/searx,PwnArt1st/searx,potato/searx,potato/searx,kdani3/searx,PwnArt1st/searx,jcherqui/searx,gugod/searx,framasoft/searx,matejc/searx,asciimoo/searx,pointhi/searx,GreenLunar/searx,potato/searx,gugod/searx,asciimoo/searx,asciimoo/searx,jpope777/searx,GreenLunar/searx,matejc/searx,jcherqui/searx,pointhi/searx,kdani3/searx,dalf/searx,misnyo/searx,dalf/searx,gugod/searx,dalf/searx