improve check for markdown library
improve check for markdown library

metallurgical/slim,Nikeshsuwal/slim,mojavelinux/slim,mojavelinux/slim,ericboehs/slim,slim-template/slim,slim-template/slim,raxoft/slim,cheunghy/slim,etdev/slim,etdev/slim,JuanitoFatas/slim,sideci-sample/sideci-sample-slim,yterajima/slim,zakuro9715/slim,XueQian/slim,fly19890211/slim,raxoft/slim,fly19890211/slim,slim-template/slim,metallurgical/slim,ruijsun/slim,ruijsun/slim,ericboehs/slim,cheunghy/slim,JuanitoFatas/slim,XueQian/slim,Nikeshsuwal/slim,zakuro9715/slim