Add category and tags pages

source/categories/index.md

@@ -0,0 +1,5 @@
+title: Categories
+date: 2016-05-20 09:25:49
+layout: categories
+comments: false
+---

source/tags/index.md

@@ -0,0 +1,5 @@
+title: Tags
+date: 2016-05-20 09:25:49
+layout: tags
+comments: false
+---