Add careers link to website (#1927)

website/site/layouts/partials/footer.html

@@ -1,6 +1,7 @@
 <footer class="text-center">
     <div class="container-fluid">
         <div class="footer__copyright">© Mattermost, Inc. All Rights Reserved.</div>
+        <div class="footer__item"><a href="https://mattermost.com/careers/?utm_source=focalboard" target="_blank">Join the team, we're hiring!</a></div>
         <div class="footer__icons">
             <a href="{{ .Site.Params.footer.facebook }}" target="_blank" rel="noopener noreferrer" class="btn-primary"><i class="fa fa-facebook"></i></a>
             <a href="{{ .Site.Params.footer.twitter }}" target="_blank" rel="noopener noreferrer" class="btn-primary"><i class="fa fa-twitter"></i></a>

website/site/layouts/partials/hero.html

@@ -36,7 +36,13 @@ <h2>
 			<p>
 				Focalboard is open source! <a href="https://github.com/mattermost/focalboard" target='_blank'>Check out the source code here</a>, and contribute to the future of this project.
 			</p>
-		</div>
+
+			<p>
+                <b>We're also hiring!</b> Focalboard was built by a passionate group here at Mattermost.
+                We're looking for more talented engineers, designers, product managers, and other roles to join our rapidly growing team.
+                Find out more on our <a href="https://mattermost.com/careers/?utm_source=focalboard" target="_blank">careers page</a>.
+            </p>
+        </div>
 
 		{{ if .Site.Params.search.enable }}
 			<div class="homepage-search row">

website/site/static/css/styles.css

@@ -3213,11 +3213,8 @@ footer {
     padding: 50px 0 40px;
 }
 
-.footer__copyright {
-    margin-bottom: 2em;
-}
-
 .footer__icons a {
+    margin-top: 2em;
     -moz-border-radius: 50%;
     -webkit-border-radius: 50%;
     border-radius: 50%;