Fix navigaton bar

Thanks to GitHub support for telling me how

_includes/header.html

@@ -15,7 +15,7 @@
 
       <div class="trigger">
         {% for page in site.pages %}
-          {% if page.title %}
+          {% if page.navigation %}
           <a class="page-link" href="{{ page.url | prepend: site.baseurl }}">{{ page.title }}</a>
           {% endif %}
         {% endfor %}

blog/index.md

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: Blog
+navigation: true
 permalink: /blog/
 excerpt: "Blog index, posts in English and posts in Finnish — Blogin etusivu, postaukset englanniksi ja postaukset suomeksi."
 ---

pages/irc/irc.markdown

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: IRC
+navigation: true
 permalink: /irc/
 excerpt: "Where do you find me at IRC and verify that it's me. Also includes my IRC related posts that are hopefully helpful and my policy on joining personal channels of other people (e.g. ##channels at freenode)."
 ---

pages/keys.markdown

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: Public keys
+navigation: true
 permalink: /keys/
 redirect_from:
   - /omemo.html

pages/some.markdown

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: Social media
+navigation: true
 permalink: /some/
 redirect_from:
   - /links/