Markdown:remove underline for h1 heading and change underline style to solid for h2 heading
Markdown:remove underline for h1 heading and change underline style to solid for h2 heading

doortts/forked-for-history,oolso/yobi,brainagenet/yobi,yona-projects/yona,ahb0327/yobi,doortts/forked-for-history,violetag/demo,doortts/fork-yobi,ihoneymon/yobi,violetag/demo,bloodybear/yona,naver/yobi,ihoneymon/yobi,ChangsungKim/TestRepository01,Limseunghwan/oss,doortts/forked-for-history,ahb0327/yobi,bloodybear/yona,ChangsungKim/TestRepository01,doortts/fork-yobi,brainagenet/yobi,bloodybear/yona,ihoneymon/yobi,oolso/yobi,yona-projects/yona,Limseunghwan/oss,yona-projects/yona,oolso/yobi,yona-projects/yona,naver/yobi,naver/yobi,ahb0327/yobi,doortts/fork-yobi,doortts/fork-yobi,Limseunghwan/oss,brainagenet/yobi,bloodybear/yona