Options page: add link to Pontoon

In order to promote Pontoon (the translation platform), this change adds
a link in the options page.

Fixed: twpowertools:42
Change-Id: I4eb6b5a0d050782e4bc236b968c3c525d8e4ebc4
diff --git a/src/static/options/options.css b/src/static/options/options.css
index 6933e13..4ab69b3 100644
--- a/src/static/options/options.css
+++ b/src/static/options/options.css
@@ -7,19 +7,21 @@
   max-width: 600px;
 }
 
-.features-link, .experiments-link {
+.featured-links {
   position: absolute;
   top: 8px;
-  width: 24px;
+  right: 8px;
+  display: flex;
+  flex-direction: row;
 }
 
-.features-link {
-  right: 8px;
+.featured-links > * {
+  width: 24px;
+  margin-left: 8px;
 }
 
 .experiments-link {
   cursor: pointer;
-  right: 40px;
 }
 
 .option {