Add links to install methods to `Readme.md`
Add links to install methods to `Readme.md`

chcokr/mdast,tanzania82/remarks,yukkurisinai/mdast,ulrikaugustsson/mdast,wooorm/remark,ulrikaugustsson/mdast,yukkurisinai/mdast,eush77/remark,eush77/remark,chcokr/mdast