Some SEO improvements

- meta description
- empty robots.txt
- changed welcome message on home to h2

- CSS in-line fold pairs

layouts/partials/hero.html

@@ -34,9 +34,9 @@
 </div>
 
 <!-- <div style="text-align: center;"> -->
-<!-- <div class="hero-tagline">
-  [>“Live, love and Linux.”<]
-  <p>Live, love and <img src="{{ "/img/linux-icon.svg" | relURL }}"
-                          class="icon"
-  alt="linux-icon"/>.</p>
-</div> -->
+<!-- <div class="hero-tagline"> -->
+  <!-- [> “Live, love and Linux.” <] -->
+  <!-- <p>Live, love and <img src="{{ "/img/linux-icon.svg" | relURL }}" -->
+                          <!-- class="icon" -->
+  <!-- alt="linux-icon"/>.</p> -->
+<!-- </div> -->