Bug 29035: Add link for newsletter sign-up

Patch based on a version written by Arthur Edelstein

src/chrome/content/aboutTor/aboutTor.xhtml

@@ -62,9 +62,12 @@ window.addEventListener("pageshow", function() {
     </div>
 
     <div id="bottom">
-      <p class="showForManual moreInfoLink">&aboutTor.torbrowser_user_manual_questions.label;
+      <p id="manual" class="showForManual moreInfoLink">&aboutTor.torbrowser_user_manual_questions.label;
         <a id="manualLink" target="_blank">&aboutTor.torbrowser_user_manual_link.label;</a></p>
-      <p>&aboutTor.tor_mission.label;
+      <p id="newsletter" class="moreInfoLink"><img class="imageStyle" src="resource://torbutton-assets/icon-newsletter.png"/><br/>&aboutTor.newsletter.tagline;<br/>
+        <a href="https://newsletter.torproject.org">&aboutTor.newsletter.link_text; &#187;</a>
+      </p>
+      <p id="mission">&aboutTor.tor_mission.label;
         <a href="&aboutTor.getInvolved.link;">&aboutTor.getInvolved.label;</a></p>
     </div>
   </div>

src/chrome/skin/aboutTor.css

@@ -149,6 +149,19 @@ body:not([showmanual]) .showForManual {
   font-size: 15px;
 }
 
+#bottom img.imageStyle {
+  padding-inline-end: 10px;
+}
+
+/* Hide the linebreaks on large enough screens (desktops, laptops, and
+ * tablets).
+ */
+@media only screen and (min-width: 768px) {
+  #bottom br {
+    display: none;
+  }
+}
+
 .searchbox form {
   width: 500px;
   margin: 39px auto 0px auto;
@@ -293,7 +306,8 @@ body:not([showmanual]) .showForManual {
 body[mobile] #torstatus-version,
 body[mobile] .searchbox,
 body[mobile] .top .heading2,
-body[mobile] #bottom {
+body[mobile] #manual,
+body[mobile] #mission {
   display: none;
 }