feat(v2): bootstrap blog post page and card (#2584)

* feat(v2): init the blog post card

* feat(v2): Update card design

* chore(v2): remove unused dependency

* feat(v2): add post list

* feat(v2): improve html tags

* chore(v2): run prettier

* feat(v2): remove old tag

* feat(v2): apply suggestions

packages/docusaurus-init/templates/bootstrap/blog/2019-05-28-hola.md

@@ -0,0 +1,11 @@
+---
+id: hola
+title: Hola
+author: Gao Wei
+author_title: Docusaurus Core Team
+author_url: https://github.com/wgao19
+author_image_url: https://avatars1.githubusercontent.com/u/2055384?v=4
+tags: [hola, docusaurus]
+---
+
+Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque elementum dignissim ultricies. Fusce rhoncus ipsum tempor eros aliquam consequat. Lorem ipsum dolor sit amet

packages/docusaurus-init/templates/bootstrap/blog/2019-05-29-hello-world.md

@@ -0,0 +1,17 @@
+---
+id: hello-world
+title: Hello
+author: Endilie Yacop Sucipto
+author_title: Maintainer of Docusaurus
+author_url: https://github.com/endiliey
+author_image_url: https://avatars1.githubusercontent.com/u/17883920?s=460&v=4
+tags: [hello, docusaurus]
+---
+
+Welcome to this blog. This blog is created with [**Docusaurus 2 alpha**](https://v2.docusaurus.io/).
+
+<!--truncate-->
+
+This is a test post.
+
+A whole bunch of other information.

packages/docusaurus-init/templates/bootstrap/blog/2019-05-30-welcome.md

@@ -0,0 +1,13 @@
+---
+id: welcome
+title: Welcome
+author: Yangshun Tay
+author_title: Front End Engineer @ Facebook
+author_url: https://github.com/yangshun
+author_image_url: https://avatars0.githubusercontent.com/u/1315101?s=400&v=4
+tags: [facebook, hello, docusaurus]
+---
+
+Blog features are powered by the blog plugin. Simply add files to the `blog` directory. It supports tags as well!
+
+Delete the whole directory if you don't want the blog features. As simple as that!