Tag some cool cheatsheets as 'featurable'

cssnext.md

@@ -3,6 +3,7 @@ title: cssnext
 category: CSS
 layout: 2017/sheet
 updated: 2017-08-30
+tags: [Featurable]
 weight: -3
 ---
 

datetime.md

@@ -3,6 +3,7 @@ title: Date & time formats
 layout: 2017/sheet
 weight: -5
 updated: 2017-09-04
+tags: [Featurable]
 ---
 
 ### Common time formats

factory_bot.md

@@ -9,6 +9,7 @@ keywords:
   - "factory :user"
   - "first_name 'John'"
   - "sequence(:username) { |n| \"user#{n}\" }"
+tags: [Featurable]
 intro: |
   [Factory Bot](http://www.rubydoc.info/gems/factory_bot/) is a helper for writing factories for Ruby tests.
   It was previously known as Factory Girl. For older versions, use `FactoryGirl` instead of `FactoryBot`.

flow.md

@@ -4,6 +4,7 @@ layout: 2017/sheet
 category: JavaScript libraries
 updated: 2017-09-20
 weight: -3
+tags: [Featurable]
 ---
 
 ## Getting started

jest.md

@@ -4,6 +4,7 @@ category: JavaScript libraries
 layout: 2017/sheet
 updated: 2017-09-01
 weight: -3
+tags: [Featurable]
 intro: |
   A quick overview to [Jest](https://facebook.github.io/jest/), a test framework for Node.js. This guide targets Jest v20.
 ---

moment.md

@@ -3,6 +3,7 @@ title: Moment.js
 category: JavaScript libraries
 layout: 2017/sheet
 updated: 2017-10-10
+tags: [Featurable]
 ---
 
 ### Parsing

yarn.md

@@ -5,6 +5,7 @@ layout: 2017/sheet
 weight: -3
 updated: 2017-09-08
 prism_languages: [json, bash]
+tags: [Featurable]
 ---
 
 ### npm equivalents