Add archives content file

Also this reverts the previous commit

content/archives.md

@@ -0,0 +1,5 @@
+---
+date: 2019-05-28
+type: section
+layout: "archives"
+---

content/post/_index.md

@@ -1,5 +1,5 @@
 +++
-aliases = ["posts","articles","blog","showcase","docs","archives"]
+aliases = ["posts","articles","blog","showcase","docs"]
 title = "Posts"
 author = "Hugo Authors"
 tags = ["index"]