Update DigitalOcean (#1753)

- Updated DigitalOcean tagline/link
- On homepage and sponsors page

app/views/articles/_sidebar.html.erb

@@ -12,12 +12,12 @@
         </header>
         <div class="widget-body">
           <div class="sidebar-sponsor">
-            <a class="partner-link" href="https://try.digitalocean.com/performance/?utm_source=devto&utm_medium=display&utm_campaign=Devto_2018_Brand" target="_blank" data-details="digitalocean__image">
+            <a class="partner-link" href="https://do.co/devto" target="_blank" data-details="digitalocean__image">
               <img src="<%= cloudinary("https://thepracticaldev.s3.amazonaws.com/i/85318v8gv77kzr8r2e58.png") %>" style="margin-bottom:8px;" alt="Digital Ocean logo" />
             </a>
             <div class="sponsor-tagline" style="display:inline;">
-              The all-in-one cloud platform developers & their teams love.
-              <a class="partner-link sponsor-learn-more" href="https://try.digitalocean.com/performance/?utm_source=devto&utm_medium=display&utm_campaign=Devto_2018_Brand" target="_blank" data-details="digitalocean__learn-more">
+              The simplest cloud platform for developers & teams.
+              <a class="partner-link sponsor-learn-more" href="https://do.co/devto" target="_blank" data-details="digitalocean__learn-more">
                 Learn More
               </a>
             </div>

app/views/pages/sponsors.html.erb

@@ -29,9 +29,9 @@
 
     <h4><img src="<%= cloudinary("https://thepracticaldev.s3.amazonaws.com/i/2zmukvll98je8qsdyewq.png", 30) %>"><span style="background-color: #fefa87; padding:3px;">Gold Sponsors</span><img src="<%= cloudinary("https://thepracticaldev.s3.amazonaws.com/i/2zmukvll98je8qsdyewq.png", 30) %>"></h4>
     <div id="gold-sponsors">
-      <a href="https://try.digitalocean.com/performance/?utm_source=devto&utm_medium=display&utm_campaign=Devto_2018_Brand"><img src="<%= cloudinary("https://thepracticaldev.s3.amazonaws.com/i/85318v8gv77kzr8r2e58.png", 250) %>"></a>
+      <a href="https://do.co/devto"><img src="<%= cloudinary("https://thepracticaldev.s3.amazonaws.com/i/85318v8gv77kzr8r2e58.png", 250) %>"></a>
 
-      <p><a href="https://try.digitalocean.com/performance/?utm_source=devto&amp;utm_medium=display&amp;utm_campaign=Devto_2018_Brand">Digital Ocean</a> is a much-loved cloud computing platform. I'm always impressed by how well-built <em>and well-documented</em> the Digital Ocean core products are. It's easier said than done, and they've been able to stay ahead of the curve.</p>
+      <p><a href="https://do.co/devto">Digital Ocean</a> is a much-loved cloud computing platform. I'm always impressed by how well-built <em>and well-documented</em> the Digital Ocean core products are. It's easier said than done, and they've been able to stay ahead of the curve.</p>
 
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