Upgrade Jekyll to 3.8

[jan0sch]

The jekyll installation is upgraded to 3.8.3. Because bundler refused to update farther than 3.6 it was necessary to remove to old Gemfile.lock and run bundle install.

So far it looks good.

This fixes #932

[ashawley]

I compared the output in _site with the old. There was very little difference. The only strange thing was the addition of a new <div> around code examples and some occasional new <span> elements. However, the code examples still rendered the same for me.

Here's an example:

--- _site/blog/2016/05/06/multiversal-equality.html	2018-07-26 14:27:09.000000000 -0400
+++ _site/blog/2016/05/06/multiversal-equality.html	2018-07-26 14:28:36.000000000 -0400
@@ -159,17 +159,15 @@
 for <em>some</em> comparisons that are always <code class="highlighter-rouge">false</code>. But the coverage is
 weak. For instance this will give a warning:</p>
 
-<div class="highlighter-rouge"><pre class="highlight"><code>scala&gt; 1 == "abc"
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>scala&gt; 1 == "abc"
 &lt;console&gt;:12: warning: comparing values of types Int and String using `==' will always yield false
-</code></pre>
-</div>
+</code></pre></div></div>
 
 <p>But this will not:</p>
 
-<div class="highlighter-rouge"><pre class="highlight"><code>scala&gt; "abc" == 1
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>scala&gt; "abc" == 1
 res2: Boolean = false
-</code></pre>
-</div>
+</code></pre></div></div>
 
 <p>There are also cases where a warning is given for a valid equality
 test that actually makes sense because the result could be <code class="highlighter-rouge">true</code>. In
@@ -194,11 +192,10 @@
 property that values of type <code class="highlighter-rouge">T</code> can be compared to values of type
 <code class="highlighter-rouge">U</code>. Here’s the definition of <code class="highlighter-rouge">Eq</code></p>
 
-<div class="highlighter-rouge"><pre class="highlight"><code>package scala
+<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">package</span> <span class="n">scala</span>
 
-trait Eq[-T, -U]
-</code></pre>
-</div>
+<span class="n">trait</span> <span class="n">Eq</span><span class="p">[-</span><span class="n">T</span><span class="p">,</span> <span class="p">-</span><span class="n">U</span><span class="p">]</span>
+</code></pre></div></div>
 
 <p>That is, <code class="highlighter-rouge">Eq</code> is a pure marker trait with two type parameters and without
 any members.  Developers can define equality classes by giving

[ashawley]

Site worked when run locally for me with Ruby 2.3.3

[SethTisue]

thank you Jens (and Aaron)!

can I interest you in submitting a similar PR over in https://github.com/scala/docs.scala-lang ?

[SethTisue]

docs.scala-lang version merged: scala/docs.scala-lang#1115 🎉