Add Obsidian to Markdown Tools Section (#1077)

README.md

@@ -143,6 +143,7 @@ Any comments, suggestions? [Let us know!](https://github.com/jaywcjlove/awesome-
 * [Marp](https://marp.app) - Markdown presentation writer with cross-platform support. [![Open-Source Software][OSS Icon]](https://github.com/yhatt/marp) ![Freeware][Freeware Icon]
 * [Marxico](https://marxi.co/) - Delicate Markdown editor for Evernote. Reliable storage and sync.
 * [MWeb](http://www.mweb.im/) - Pro Markdown writing, and static blog generator App.
+* [Obsidian](https://obsidian.md) - A second brain, for you, forever.
 * [TextNut](http://www.textnutwriter.com/) - Rich-format editor featuring Markdown export and Markdown syntax hints. ![Freeware][Freeware Icon]
 * [Typora](http://www.typora.io/) - Truly minimal Markdown editor featuring seamless live preview. ![Freeware][Freeware Icon]
 * [Ulysses](https://www.ulyssesapp.com/features/) - The Ultimate Writing App for Mac, iPad and iPhone.