docs(typography): update description of the section "Changing the fon…

…t stack"

this applies the suggested changed of this review :
#212 (comment)

pug/page-contents/typography_content.html

@@ -52,8 +52,8 @@ <h3 class="header">Flow Text</h3>
         <div id="fontstack" class="section scrollspy">
           <h2 class="header">Changing the font stack</h2>
           <p class="caption">
-            The standard font Material Design uses is Roboto. We have included the font files with our framework.
-            <br>In case you don't want to use Roboto on your webpage, fear not. Simply change the font stack by modifying the
+            The Material Design standard uses Roboto font. We have included the font in our framework.
+            <br>In case you don't want to use Roboto on your webpage, fear not. You can change the font stack by modifying the
             code below to your liking and add it to your custom CSS.
           </p>
           <pre><code class="language-css">