Add theme concise

Author: yingyu5658

themes.txt

@@ -514,6 +514,7 @@ github.com/Xzya/hugo-material-blog
 github.com/yanlinlin82/simple-style
 github.com/yihui/hugo-xmag
 github.com/yihui/hugo-xmin
+github.com/yingyu5658/hugo-theme-concise
 github.com/yoshiharuyamashita/blackburn
 github.com/your-identity/hugo-theme-dimension
 github.com/yue1124/hero