Simpler headers

Signed-off-by: Valentin Popov <valentineus@gmail.com>

_pages/404.md

@@ -1,10 +1,7 @@
 ---
-permalink:      "/404.html"
-layout:         page
-sidebar:        false
-id:             404
-title:          "404: Page not found"
-description:    ""
+permalink: "/404.html"
+title: "404: Page not found"
+layout: page
 ---
 
 Sorry, we've misplaced that URL or it's pointing to something that doesn't exist.

_pages/about.md

@@ -1,10 +1,9 @@
 ---
-permalink:      "/about.html"
-layout:         page
-sidebar:        true
-id:             about
-title:          "About"
-description:    "Обо мне"
+permalink: "/about.html"
+description: "Обо мне"
+title: "About"
+sidebar: true
+layout: page
 ---
 
 There is a significant amount of subtle, yet precisely calibrated, styling to ensure that your content is emphasized while still looking aesthetically pleasing.

_pages/atom.md

@@ -1,7 +1,6 @@
 ---
-layout:    null
 permalink: "/atom.xml"
-sidebar:   false
+layout: null
 ---
 
 <?xml version="1.0" encoding="utf-8"?>

_pages/index.md

@@ -1,8 +1,9 @@
 ---
-permalink:    "/index.html"
-layout:       default
-title:        "Home"
-id:           index
+permalink: "/index.html"
+layout: default
+sidebar: true
+title: "Home"
+id: index
 ---
 
 <div class="page">